81630772 has 12 divisors (see below), whose sum is σ = 149065056. Its totient is φ = 39040760.

The previous prime is 81630767. The next prime is 81630793. The reversal of 81630772 is 27703618.

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, 443554 + ... + 443737.

It is an arithmetic number, because the mean of its divisors is an integer number (12422088).

Almost surely, 2^81630772 is an apocalyptic number.

It is an amenable number.

81630772 is a deficient number, since it is larger than the sum of its proper divisors (67434284).

81630772 is a wasteful number, since it uses less digits than its factorization.

81630772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 887318 (or 887316 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 81630772 is about 9034.9749307898. The cubic root of 81630772 is about 433.7950925224.

The spelling of 81630772 in words is "eighty-one million, six hundred thirty thousand, seven hundred seventy-two".