621064537 has 2 divisors, whose sum is σ = 621064538. Its totient is φ = 621064536.

The previous prime is 621064513. The next prime is 621064541. The reversal of 621064537 is 735460126.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 314849536 + 306215001 = 17744^2 + 17499^2 .

It is a cyclic number.

It is not a de Polignac number, because 621064537 - 2¹⁵ = 621031769 is a prime.

It is not a weakly prime, because it can be changed into another prime (621064567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310532268 + 310532269.

It is an arithmetic number, because the mean of its divisors is an integer number (310532269).

Almost surely, 2^621064537 is an apocalyptic number.

It is an amenable number.

621064537 is a deficient number, since it is larger than the sum of its proper divisors (1).

621064537 is an equidigital number, since it uses as much as digits as its factorization.

621064537 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 34.

The square root of 621064537 is about 24921.1664454134. The cubic root of 621064537 is about 853.1896476247.

The spelling of 621064537 in words is "six hundred twenty-one million, sixty-four thousand, five hundred thirty-seven".