81370100 has 36 divisors (see below), whose sum is σ = 201799584. Its totient is φ = 27898080.

The previous prime is 81370097. The next prime is 81370123. The reversal of 81370100 is 107318.

It is a super-3 number, since 3×81370100³ (a number of 25 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

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, 57422 + ... + 58821.

It is an arithmetic number, because the mean of its divisors is an integer number (5605544).

Almost surely, 2^81370100 is an apocalyptic number.

It is an amenable number.

81370100 is an abundant number, since it is smaller than the sum of its proper divisors (120429484).

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

81370100 is a wasteful number, since it uses less digits than its factorization.

81370100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116264 (or 116257 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 20.

The square root of 81370100 is about 9020.5376779879. The cubic root of 81370100 is about 433.3328533854.

Adding to 81370100 its reverse (107318), we get a palindrome (81477418).

The spelling of 81370100 in words is "eighty-one million, three hundred seventy thousand, one hundred".