81200625 has 80 divisors (see below), whose sum is σ = 153550848. Its totient is φ = 37800000.

The previous prime is 81200621. The next prime is 81200627. The reversal of 81200625 is 52600218.

It is not a de Polignac number, because 81200625 - 2² = 81200621 is a prime.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 81200595 and 81200604.

It is not an unprimeable number, because it can be changed into a prime (81200621) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 639312 + ... + 639438.

Almost surely, 2^81200625 is an apocalyptic number.

It is an amenable number.

81200625 is a deficient number, since it is larger than the sum of its proper divisors (72350223).

81200625 is a wasteful number, since it uses less digits than its factorization.

81200625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 81200625 is about 9011.1389402228. The cubic root of 81200625 is about 433.0318004191.

The spelling of 81200625 in words is "eighty-one million, two hundred thousand, six hundred twenty-five".