1257896640 has 1008 divisors, whose sum is σ = 5822935776. Its totient is φ = 227082240.

The previous prime is 1257896639. The next prime is 1257896683. The reversal of 1257896640 is 466987521.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 1257896640.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 73993912 + ... + 73993928.

It is an arithmetic number, because the mean of its divisors is an integer number (5776722).

Almost surely, 2^1257896640 is an apocalyptic number.

1257896640 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 1257896640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2911467888).

1257896640 is an abundant number, since it is smaller than the sum of its proper divisors (4565039136).

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

1257896640 is a wasteful number, since it uses less digits than its factorization.

1257896640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86 (or 58 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 48.

The square root of 1257896640 is about 35466.8385960745. The cubic root of 1257896640 is about 1079.4809577241.

The spelling of 1257896640 in words is "one billion, two hundred fifty-seven million, eight hundred ninety-six thousand, six hundred forty".