81616976 has 20 divisors (see below), whose sum is σ = 180723552. Its totient is φ = 34978656.

The previous prime is 81616973. The next prime is 81616981. The reversal of 81616976 is 67961618.

It is a super-2 number, since 2×81616976² = 13322661542769152, which contains 22 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81616973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 364250 + ... + 364473.

Almost surely, 2^81616976 is an apocalyptic number.

It is an amenable number.

81616976 is an abundant number, since it is smaller than the sum of its proper divisors (99106576).

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

81616976 is a wasteful number, since it uses less digits than its factorization.

81616976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728738 (or 728732 counting only the distinct ones).

The product of its digits is 108864, while the sum is 44.

The square root of 81616976 is about 9034.2114210373. The cubic root of 81616976 is about 433.7706533143.

The spelling of 81616976 in words is "eighty-one million, six hundred sixteen thousand, nine hundred seventy-six".