72575021 has 2 divisors, whose sum is σ = 72575022. Its totient is φ = 72575020.

The previous prime is 72575017. The next prime is 72575033. The reversal of 72575021 is 12057527.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39062500 + 33512521 = 6250^2 + 5789^2 .

It is a cyclic number.

It is not a de Polignac number, because 72575021 - 2² = 72575017 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_4260593 and since 72575021 and 4260593 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72575071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36287510 + 36287511.

It is an arithmetic number, because the mean of its divisors is an integer number (36287511).

Almost surely, 2^72575021 is an apocalyptic number.

It is an amenable number.

72575021 is a deficient number, since it is larger than the sum of its proper divisors (1).

72575021 is an equidigital number, since it uses as much as digits as its factorization.

72575021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4900, while the sum is 29.

The square root of 72575021 is about 8519.0974287186. The cubic root of 72575021 is about 417.1213218102.

The spelling of 72575021 in words is "seventy-two million, five hundred seventy-five thousand, twenty-one".