72721122 has 16 divisors (see below), whose sum is σ = 145548480. Its totient is φ = 24222672.

The previous prime is 72721109. The next prime is 72721123. The reversal of 72721122 is 22112727.

It is a junction number, because it is equal to n+sod(n) for n = 72721092 and 72721101.

It is not an unprimeable number, because it can be changed into a prime (72721123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6579 + ... + 13737.

It is an arithmetic number, because the mean of its divisors is an integer number (9096780).

Almost surely, 2^72721122 is an apocalyptic number.

72721122 is an abundant number, since it is smaller than the sum of its proper divisors (72827358).

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

72721122 is a wasteful number, since it uses less digits than its factorization.

72721122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8857.

The product of its digits is 784, while the sum is 24.

The square root of 72721122 is about 8527.6680282478. The cubic root of 72721122 is about 417.4010369381.

Adding to 72721122 its reverse (22112727), we get a palindrome (94833849).

The spelling of 72721122 in words is "seventy-two million, seven hundred twenty-one thousand, one hundred twenty-two".