64220731 has 2 divisors, whose sum is σ = 64220732. Its totient is φ = 64220730.

The previous prime is 64220711. The next prime is 64220743. The reversal of 64220731 is 13702246.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 64220731 - 2⁵ = 64220699 is a prime.

It is a super-2 number, since 2×64220731² = 8248604580348722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 64220696 and 64220705.

It is not a weakly prime, because it can be changed into another prime (64220701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32110365 + 32110366.

It is an arithmetic number, because the mean of its divisors is an integer number (32110366).

Almost surely, 2^64220731 is an apocalyptic number.

64220731 is a deficient number, since it is larger than the sum of its proper divisors (1).

64220731 is an equidigital number, since it uses as much as digits as its factorization.

64220731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 64220731 is about 8013.7838129064. The cubic root of 64220731 is about 400.4593285912.

Adding to 64220731 its reverse (13702246), we get a palindrome (77922977).

The spelling of 64220731 in words is "sixty-four million, two hundred twenty thousand, seven hundred thirty-one".