64391633 has 2 divisors, whose sum is σ = 64391634. Its totient is φ = 64391632.

The previous prime is 64391603. The next prime is 64391653. The reversal of 64391633 is 33619346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64368529 + 23104 = 8023^2 + 152^2 .

It is a cyclic number.

It is not a de Polignac number, because 64391633 - 2¹⁸ = 64129489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 64391593 and 64391602.

It is not a weakly prime, because it can be changed into another prime (64391603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32195816 + 32195817.

It is an arithmetic number, because the mean of its divisors is an integer number (32195817).

Almost surely, 2^64391633 is an apocalyptic number.

It is an amenable number.

64391633 is a deficient number, since it is larger than the sum of its proper divisors (1).

64391633 is an equidigital number, since it uses as much as digits as its factorization.

64391633 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34992, while the sum is 35.

The square root of 64391633 is about 8024.4397312211. The cubic root of 64391633 is about 400.8142434776.

The spelling of 64391633 in words is "sixty-four million, three hundred ninety-one thousand, six hundred thirty-three".