72881820 has 72 divisors (see below), whose sum is σ = 241179120. Its totient is φ = 17667840.

The previous prime is 72881807. The next prime is 72881821. The reversal of 72881820 is 2818827.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72881821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16425 + ... + 20384.

It is an arithmetic number, because the mean of its divisors is an integer number (3349710).

Almost surely, 2^72881820 is an apocalyptic number.

It is an amenable number.

72881820 is an abundant number, since it is smaller than the sum of its proper divisors (168297300).

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

72881820 is a wasteful number, since it uses less digits than its factorization.

72881820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36835 (or 36830 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 36.

The square root of 72881820 is about 8537.0849825921. The cubic root of 72881820 is about 417.7082661772.

The spelling of 72881820 in words is "seventy-two million, eight hundred eighty-one thousand, eight hundred twenty".