72196121 has 4 divisors (see below), whose sum is σ = 73957044. Its totient is φ = 70435200.

The previous prime is 72196087. The next prime is 72196147. The reversal of 72196121 is 12169127.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 25806400 + 46389721 = 5080^2 + 6811^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72196121 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72196151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 880400 + ... + 880481.

It is an arithmetic number, because the mean of its divisors is an integer number (18489261).

Almost surely, 2^72196121 is an apocalyptic number.

It is an amenable number.

72196121 is a deficient number, since it is larger than the sum of its proper divisors (1760923).

72196121 is a wasteful number, since it uses less digits than its factorization.

72196121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1760922.

The product of its digits is 1512, while the sum is 29.

The square root of 72196121 is about 8496.8300559679. The cubic root of 72196121 is about 416.3941519023.

The spelling of 72196121 in words is "seventy-two million, one hundred ninety-six thousand, one hundred twenty-one".