72691537 has 2 divisors, whose sum is σ = 72691538. Its totient is φ = 72691536.

The previous prime is 72691519. The next prime is 72691561. The reversal of 72691537 is 73519627.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68707521 + 3984016 = 8289^2 + 1996^2 .

It is an emirp because it is prime and its reverse (73519627) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72691537 - 2¹¹ = 72689489 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72691537.

It is not a weakly prime, because it can be changed into another prime (72691637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36345768 + 36345769.

It is an arithmetic number, because the mean of its divisors is an integer number (36345769).

Almost surely, 2^72691537 is an apocalyptic number.

It is an amenable number.

72691537 is a deficient number, since it is larger than the sum of its proper divisors (1).

72691537 is an equidigital number, since it uses as much as digits as its factorization.

72691537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 79380, while the sum is 40.

The square root of 72691537 is about 8525.9332040546. The cubic root of 72691537 is about 417.3444257623.

The spelling of 72691537 in words is "seventy-two million, six hundred ninety-one thousand, five hundred thirty-seven".