81692688 has 240 divisors, whose sum is σ = 283696128. Its totient is φ = 19641600.

The previous prime is 81692683. The next prime is 81692713. The reversal of 81692688 is 88629618.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (81692683) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2635233 + ... + 2635263.

Almost surely, 2^81692688 is an apocalyptic number.

81692688 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81692688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141848064).

81692688 is an abundant number, since it is smaller than the sum of its proper divisors (202003440).

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

81692688 is a wasteful number, since it uses less digits than its factorization.

81692688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 77 counting only the distinct ones).

The product of its digits is 331776, while the sum is 48.

The square root of 81692688 is about 9038.4007434944. The cubic root of 81692688 is about 433.9047409978.

The spelling of 81692688 in words is "eighty-one million, six hundred ninety-two thousand, six hundred eighty-eight".