81302155 has 16 divisors (see below), whose sum is σ = 108025344. Its totient is φ = 58243680.

The previous prime is 81302149. The next prime is 81302173. The reversal of 81302155 is 55120318.

It is a happy number.

It is not a de Polignac number, because 81302155 - 2⁹ = 81301643 is a prime.

It is a super-2 number, since 2×81302155² = 13220080815288050, which contains 22 as substring.

It is a Duffinian number.

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, 7347 + ... + 14716.

It is an arithmetic number, because the mean of its divisors is an integer number (6751584).

Almost surely, 2^81302155 is an apocalyptic number.

81302155 is a deficient number, since it is larger than the sum of its proper divisors (26723189).

81302155 is a wasteful number, since it uses less digits than its factorization.

81302155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22146.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 81302155 is about 9016.7707634164. The cubic root of 81302155 is about 433.2122071056.

The spelling of 81302155 in words is "eighty-one million, three hundred two thousand, one hundred fifty-five".