81966960 has 60 divisors (see below), whose sum is σ = 275274792. Its totient is φ = 21857664.

The previous prime is 81966949. The next prime is 81966971. The reversal of 81966960 is 6966918.

It is an interprime number because it is at equal distance from previous prime (81966949) and next prime (81966971).

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 56202 + ... + 57641.

Almost surely, 2^81966960 is an apocalyptic number.

81966960 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81966960 is an abundant number, since it is smaller than the sum of its proper divisors (193307832).

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

81966960 is a wasteful number, since it uses less digits than its factorization.

81966960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113862 (or 113853 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 81966960 is about 9053.5606255219. The cubic root of 81966960 is about 434.3897904665.

The spelling of 81966960 in words is "eighty-one million, nine hundred sixty-six thousand, nine hundred sixty".