1299999456 has 336 divisors, whose sum is σ = 4627324800. Its totient is φ = 351039744.

The previous prime is 1299999419. The next prime is 1299999473. The reversal of 1299999456 is 6549999921.

It is a happy number.

1299999456 is a `hidden beast` number, since 1 + 2 + 9 + 99 + 99 + 456 = 666.

1299999456 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 1299999393 and 1299999402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 3102415 + ... + 3102833.

It is an arithmetic number, because the mean of its divisors is an integer number (13771800).

Almost surely, 2^1299999456 is an apocalyptic number.

1299999456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1299999456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2313662400).

1299999456 is an abundant number, since it is smaller than the sum of its proper divisors (3327325344).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1299999456 is an equidigital number, since it uses as much as digits as its factorization.

1299999456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473 (or 450 counting only the distinct ones).

The product of its digits is 14171760, while the sum is 63.

The square root of 1299999456 is about 36055.5052107164. The cubic root of 1299999456 is about 1091.3927308258.

The spelling of 1299999456 in words is "one billion, two hundred ninety-nine million, nine hundred ninety-nine thousand, four hundred fifty-six".