81511662 has 16 divisors (see below), whose sum is σ = 163660752. Its totient is φ = 27064320.

The previous prime is 81511631. The next prime is 81511669. The reversal of 81511662 is 26611518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81511669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24889 + ... + 27972.

It is an arithmetic number, because the mean of its divisors is an integer number (10228797).

Almost surely, 2^81511662 is an apocalyptic number.

81511662 is an abundant number, since it is smaller than the sum of its proper divisors (82149090).

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

81511662 is a wasteful number, since it uses less digits than its factorization.

81511662 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53123.

The product of its digits is 2880, while the sum is 30.

The square root of 81511662 is about 9028.3809179719. The cubic root of 81511662 is about 433.5840018459.

The spelling of 81511662 in words is "eighty-one million, five hundred eleven thousand, six hundred sixty-two".