81925308 has 18 divisors (see below), whose sum is σ = 207089064. Its totient is φ = 27308424.

The previous prime is 81925303. The next prime is 81925309. The reversal of 81925308 is 80352918.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 2275703 = 81925308 / (8 + 1 + 9 + 2 + 5 + 3 + 0 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81925303) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1137816 + ... + 1137887.

It is an arithmetic number, because the mean of its divisors is an integer number (11504948).

Almost surely, 2^81925308 is an apocalyptic number.

It is an amenable number.

81925308 is an abundant number, since it is smaller than the sum of its proper divisors (125163756).

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

81925308 is a wasteful number, since it uses less digits than its factorization.

81925308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2275713 (or 2275708 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 81925308 is about 9051.2600227814. The cubic root of 81925308 is about 434.3161987447.

The spelling of 81925308 in words is "eighty-one million, nine hundred twenty-five thousand, three hundred eight".