65621539 has 2 divisors, whose sum is σ = 65621540. Its totient is φ = 65621538.

The previous prime is 65621533. The next prime is 65621551. The reversal of 65621539 is 93512656.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 65621539 - 2³ = 65621531 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 65621498 and 65621507.

It is not a weakly prime, because it can be changed into another prime (65621531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32810769 + 32810770.

It is an arithmetic number, because the mean of its divisors is an integer number (32810770).

Almost surely, 2^65621539 is an apocalyptic number.

65621539 is a deficient number, since it is larger than the sum of its proper divisors (1).

65621539 is an equidigital number, since it uses as much as digits as its factorization.

65621539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48600, while the sum is 37.

The square root of 65621539 is about 8100.7122526356. The cubic root of 65621539 is about 403.3500704906.

The spelling of 65621539 in words is "sixty-five million, six hundred twenty-one thousand, five hundred thirty-nine".