857641680 has 120 divisors (see below), whose sum is σ = 3291729792. Its totient is φ = 196031232.

The previous prime is 857641669. The next prime is 857641717. The reversal of 857641680 is 86146758.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80044 + ... + 90123.

Almost surely, 2^857641680 is an apocalyptic number.

857641680 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

857641680 is an abundant number, since it is smaller than the sum of its proper divisors (2434088112).

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

857641680 is a wasteful number, since it uses less digits than its factorization.

857641680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170193 (or 170184 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The square root of 857641680 is about 29285.5199714808. The cubic root of 857641680 is about 950.0984865578.

The spelling of 857641680 in words is "eight hundred fifty-seven million, six hundred forty-one thousand, six hundred eighty".