82156640 has 24 divisors (see below), whose sum is σ = 194095440. Its totient is φ = 32862592.

The previous prime is 82156619. The next prime is 82156651. The reversal of 82156640 is 4665128.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 82156597 and 82156606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256580 + ... + 256899.

It is an arithmetic number, because the mean of its divisors is an integer number (8087310).

Almost surely, 2^82156640 is an apocalyptic number.

82156640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

82156640 is an abundant number, since it is smaller than the sum of its proper divisors (111938800).

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

82156640 is a wasteful number, since it uses less digits than its factorization.

82156640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513494 (or 513486 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 82156640 is about 9064.0300087764. The cubic root of 82156640 is about 434.7246065930.

The spelling of 82156640 in words is "eighty-two million, one hundred fifty-six thousand, six hundred forty".