81940616 has 32 divisors (see below), whose sum is σ = 164484000. Its totient is φ = 38151936.

The previous prime is 81940577. The next prime is 81940619. The reversal of 81940616 is 61604918.

It is not an unprimeable number, because it can be changed into a prime (81940619) 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, 4400 + ... + 13536.

It is an arithmetic number, because the mean of its divisors is an integer number (5140125).

Almost surely, 2^81940616 is an apocalyptic number.

It is an amenable number.

81940616 is an abundant number, since it is smaller than the sum of its proper divisors (82543384).

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

81940616 is a wasteful number, since it uses less digits than its factorization.

81940616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9221 (or 9217 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 81940616 is about 9052.1056114033. The cubic root of 81940616 is about 434.3432481734.

The spelling of 81940616 in words is "eighty-one million, nine hundred forty thousand, six hundred sixteen".