72293521 has 2 divisors, whose sum is σ = 72293522. Its totient is φ = 72293520.

The previous prime is 72293489. The next prime is 72293527. The reversal of 72293521 is 12539227.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72063121 + 230400 = 8489^2 + 480^2 .

It is a cyclic number.

It is not a de Polignac number, because 72293521 - 2⁵ = 72293489 is a prime.

It is not a weakly prime, because it can be changed into another prime (72293527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36146760 + 36146761.

It is an arithmetic number, because the mean of its divisors is an integer number (36146761).

Almost surely, 2^72293521 is an apocalyptic number.

It is an amenable number.

72293521 is a deficient number, since it is larger than the sum of its proper divisors (1).

72293521 is an equidigital number, since it uses as much as digits as its factorization.

72293521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7560, while the sum is 31.

The square root of 72293521 is about 8502.5596734160. The cubic root of 72293521 is about 416.5813206175.

The spelling of 72293521 in words is "seventy-two million, two hundred ninety-three thousand, five hundred twenty-one".