1299217920 has 640 divisors, whose sum is σ = 5609640960. Its totient is φ = 249200640.

The previous prime is 1299217897. The next prime is 1299217921. The reversal of 1299217920 is 297129921.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1299217921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 99939834 + ... + 99939846.

It is an arithmetic number, because the mean of its divisors is an integer number (8765064).

Almost surely, 2^1299217920 is an apocalyptic number.

1299217920 is a gapful number since it is divisible by the number (10) 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 1299217920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2804820480).

1299217920 is an abundant number, since it is smaller than the sum of its proper divisors (4310423040).

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

1299217920 is an equidigital number, since it uses as much as digits as its factorization.

1299217920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 42.

The square root of 1299217920 is about 36044.6656247495. The cubic root of 1299217920 is about 1091.1739785048.

The spelling of 1299217920 in words is "one billion, two hundred ninety-nine million, two hundred seventeen thousand, nine hundred twenty".