81352918 has 4 divisors (see below), whose sum is σ = 122029380. Its totient is φ = 40676458.

The previous prime is 81352907. The next prime is 81352919. The reversal of 81352918 is 81925318.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×81352918² = 13236594534229448, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81352919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20338228 + ... + 20338231.

It is an arithmetic number, because the mean of its divisors is an integer number (30507345).

Almost surely, 2^81352918 is an apocalyptic number.

81352918 is a deficient number, since it is larger than the sum of its proper divisors (40676462).

81352918 is a wasteful number, since it uses less digits than its factorization.

81352918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40676461.

The product of its digits is 17280, while the sum is 37.

The square root of 81352918 is about 9019.5852454534. The cubic root of 81352918 is about 433.3023505790.

The spelling of 81352918 in words is "eighty-one million, three hundred fifty-two thousand, nine hundred eighteen".