857633840 has 80 divisors (see below), whose sum is σ = 2299192128. Its totient is φ = 291422208.

The previous prime is 857633809. The next prime is 857633851. The reversal of 857633840 is 48336758.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 857633791 and 857633800.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56504 + ... + 70056.

Almost surely, 2^857633840 is an apocalyptic number.

857633840 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 857633840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1149596064).

857633840 is an abundant number, since it is smaller than the sum of its proper divisors (1441558288).

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

857633840 is a wasteful number, since it uses less digits than its factorization.

857633840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13686 (or 13680 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 44.

The square root of 857633840 is about 29285.3861166282. The cubic root of 857633840 is about 950.0955914890.

The spelling of 857633840 in words is "eight hundred fifty-seven million, six hundred thirty-three thousand, eight hundred forty".