81418770 has 40 divisors (see below), whose sum is σ = 218928204. Its totient is φ = 21711456.

The previous prime is 81418709. The next prime is 81418807. The reversal of 81418770 is 7781418.

It can be written as a sum of positive squares in 2 ways, for example, as 69906321 + 11512449 = 8361^2 + 3393^2 .

It is a super-2 number, since 2×81418770² = 13258032216625800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 49449 + ... + 51068.

Almost surely, 2^81418770 is an apocalyptic number.

81418770 is an abundant number, since it is smaller than the sum of its proper divisors (137509434).

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

81418770 is a wasteful number, since it uses less digits than its factorization.

81418770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100536 (or 100527 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 36.

The square root of 81418770 is about 9023.2350074682. The cubic root of 81418770 is about 433.4192328067.

The spelling of 81418770 in words is "eighty-one million, four hundred eighteen thousand, seven hundred seventy".