81972922 has 8 divisors (see below), whose sum is σ = 123163776. Its totient is φ = 40918332.

The previous prime is 81972911. The next prime is 81972949. The reversal of 81972922 is 22927918.

It is a sphenic number, since it is the product of 3 distinct primes.

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, 32548 + ... + 34975.

It is an arithmetic number, because the mean of its divisors is an integer number (15395472).

Almost surely, 2^81972922 is an apocalyptic number.

81972922 is a deficient number, since it is larger than the sum of its proper divisors (41190854).

81972922 is a wasteful number, since it uses less digits than its factorization.

81972922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68132.

The product of its digits is 36288, while the sum is 40.

The square root of 81972922 is about 9053.8898822550. The cubic root of 81972922 is about 434.4003222268.

The spelling of 81972922 in words is "eighty-one million, nine hundred seventy-two thousand, nine hundred twenty-two".