72981956 has 6 divisors (see below), whose sum is σ = 127718430. Its totient is φ = 36490976.

The previous prime is 72981943. The next prime is 72981971. The reversal of 72981956 is 65918927.

It can be written as a sum of positive squares in only one way, i.e., 71132356 + 1849600 = 8434^2 + 1360^2 .

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 72981956.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9122741 + ... + 9122748.

It is an arithmetic number, because the mean of its divisors is an integer number (21286405).

Almost surely, 2^72981956 is an apocalyptic number.

It is an amenable number.

72981956 is a deficient number, since it is larger than the sum of its proper divisors (54736474).

72981956 is a wasteful number, since it uses less digits than its factorization.

72981956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18245493 (or 18245491 counting only the distinct ones).

The product of its digits is 272160, while the sum is 47.

The square root of 72981956 is about 8542.9477348278. The cubic root of 72981956 is about 417.8994820990.

It can be divided in two parts, 72981 and 956, that added together give a palindrome (73937).

The spelling of 72981956 in words is "seventy-two million, nine hundred eighty-one thousand, nine hundred fifty-six".