81750156 has 12 divisors (see below), whose sum is σ = 190750392. Its totient is φ = 27250048.

The previous prime is 81750133. The next prime is 81750167. The reversal of 81750156 is 65105718.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3406245 + ... + 3406268.

It is an arithmetic number, because the mean of its divisors is an integer number (15895866).

Almost surely, 2^81750156 is an apocalyptic number.

It is an amenable number.

81750156 is an abundant number, since it is smaller than the sum of its proper divisors (109000236).

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

81750156 is a wasteful number, since it uses less digits than its factorization.

81750156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6812520 (or 6812518 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 33.

The square root of 81750156 is about 9041.5792868282. The cubic root of 81750156 is about 434.0064628427.

The spelling of 81750156 in words is "eighty-one million, seven hundred fifty thousand, one hundred fifty-six".