72431666 has 16 divisors (see below), whose sum is σ = 111555360. Its totient is φ = 35250720.

The previous prime is 72431663. The next prime is 72431677. The reversal of 72431666 is 66613427.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72431663) 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, 50045 + ... + 51471.

It is an arithmetic number, because the mean of its divisors is an integer number (6972210).

Almost surely, 2^72431666 is an apocalyptic number.

72431666 is a deficient number, since it is larger than the sum of its proper divisors (39123694).

72431666 is a wasteful number, since it uses less digits than its factorization.

72431666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2089.

The product of its digits is 36288, while the sum is 35.

The square root of 72431666 is about 8510.6795263363. The cubic root of 72431666 is about 416.8464988715.

The spelling of 72431666 in words is "seventy-two million, four hundred thirty-one thousand, six hundred sixty-six".