81430872 has 16 divisors (see below), whose sum is σ = 203577240. Its totient is φ = 27143616.

The previous prime is 81430847. The next prime is 81430883. The reversal of 81430872 is 27803418.

It is a congruent number.

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, 1696453 + ... + 1696500.

Almost surely, 2^81430872 is an apocalyptic number.

It is an amenable number.

81430872 is an abundant number, since it is smaller than the sum of its proper divisors (122146368).

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

81430872 is a wasteful number, since it uses less digits than its factorization.

81430872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3392962 (or 3392958 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 81430872 is about 9023.9055846125. The cubic root of 81430872 is about 433.4407060685.

The spelling of 81430872 in words is "eighty-one million, four hundred thirty thousand, eight hundred seventy-two".