81797902 has 8 divisors (see below), whose sum is σ = 126654912. Its totient is φ = 39579600.

The previous prime is 81797879. The next prime is 81797927. The reversal of 81797902 is 20979718.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

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, 659599 + ... + 659722.

It is an arithmetic number, because the mean of its divisors is an integer number (15831864).

Almost surely, 2^81797902 is an apocalyptic number.

81797902 is a deficient number, since it is larger than the sum of its proper divisors (44857010).

81797902 is a wasteful number, since it uses less digits than its factorization.

81797902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1319354.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 81797902 is about 9044.2192587310. The cubic root of 81797902 is about 434.0909399074.

The spelling of 81797902 in words is "eighty-one million, seven hundred ninety-seven thousand, nine hundred two".