857139978240 has 2240 divisors, whose sum is σ = 4028374715904. Its totient is φ = 169189834752.

The previous prime is 857139978229. The next prime is 857139978269. The reversal of 857139978240 is 42879931758.

857139978240 is a `hidden beast` number, since 8 + 571 + 39 + 9 + 7 + 8 + 24 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2240).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 5132574637 + ... + 5132574803.

Almost surely, 2^857139978240 is an apocalyptic number.

857139978240 is a gapful number since it is divisible by the number (80) 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 857139978240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2014187357952).

857139978240 is an abundant number, since it is smaller than the sum of its proper divisors (3171234737664).

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

857139978240 is a wasteful number, since it uses less digits than its factorization.

857139978240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247 (or 214 counting only the distinct ones).

The product of its (nonzero) digits is 30481920, while the sum is 63.

The spelling of 857139978240 in words is "eight hundred fifty-seven billion, one hundred thirty-nine million, nine hundred seventy-eight thousand, two hundred forty".