1249145856 has 396 divisors, whose sum is σ = 4444249888. Its totient is φ = 330891264.

The previous prime is 1249145831. The next prime is 1249145857. The reversal of 1249145856 is 6585419421.

1249145856 is a `hidden beast` number, since 12 + 49 + 14 + 585 + 6 = 666.

Its product of digits (345600) is a multiple of the sum of its prime divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1249145857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 18643935 + ... + 18644001.

Almost surely, 2^1249145856 is an apocalyptic number.

1249145856 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 1249145856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2222124944).

1249145856 is an abundant number, since it is smaller than the sum of its proper divisors (3195104032).

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

1249145856 is a wasteful number, since it uses less digits than its factorization.

1249145856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 96 counting only the distinct ones).

The product of its digits is 345600, while the sum is 45.

The square root of 1249145856 is about 35343.2575748190. The cubic root of 1249145856 is about 1076.9719294469.

The spelling of 1249145856 in words is "one billion, two hundred forty-nine million, one hundred forty-five thousand, eight hundred fifty-six".