72999557173 has 2 divisors, whose sum is σ = 72999557174. Its totient is φ = 72999557172.

The previous prime is 72999557153. The next prime is 72999557179. The reversal of 72999557173 is 37175599927.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61812898884 + 11186658289 = 248622^2 + 105767^2 .

It is an emirp because it is prime and its reverse (37175599927) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72999557173 - 2⁹ = 72999556661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72999557179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36499778586 + 36499778587.

It is an arithmetic number, because the mean of its divisors is an integer number (36499778587).

Almost surely, 2^72999557173 is an apocalyptic number.

It is an amenable number.

72999557173 is a deficient number, since it is larger than the sum of its proper divisors (1).

72999557173 is an equidigital number, since it uses as much as digits as its factorization.

72999557173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37507050, while the sum is 64.

The spelling of 72999557173 in words is "seventy-two billion, nine hundred ninety-nine million, five hundred fifty-seven thousand, one hundred seventy-three".