81702428 has 6 divisors (see below), whose sum is σ = 142979256. Its totient is φ = 40851212.

The previous prime is 81702427. The next prime is 81702443. The reversal of 81702428 is 82420718.

It is a junction number, because it is equal to n+sod(n) for n = 81702394 and 81702403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81702427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10212800 + ... + 10212807.

It is an arithmetic number, because the mean of its divisors is an integer number (23829876).

Almost surely, 2^81702428 is an apocalyptic number.

It is an amenable number.

81702428 is a deficient number, since it is larger than the sum of its proper divisors (61276828).

81702428 is a wasteful number, since it uses less digits than its factorization.

81702428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20425611 (or 20425609 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 81702428 is about 9038.9395395699. The cubic root of 81702428 is about 433.9219847452.

The spelling of 81702428 in words is "eighty-one million, seven hundred two thousand, four hundred twenty-eight".