64731409 has 2 divisors, whose sum is σ = 64731410. Its totient is φ = 64731408.

The previous prime is 64731397. The next prime is 64731413. The reversal of 64731409 is 90413746.

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., 56205009 + 8526400 = 7497^2 + 2920^2 .

It is a cyclic number.

It is not a de Polignac number, because 64731409 - 2⁵ = 64731377 is a prime.

It is a super-2 number, since 2×64731409² = 8380310622250562, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (64731449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32365704 + 32365705.

It is an arithmetic number, because the mean of its divisors is an integer number (32365705).

Almost surely, 2^64731409 is an apocalyptic number.

It is an amenable number.

64731409 is a deficient number, since it is larger than the sum of its proper divisors (1).

64731409 is an equidigital number, since it uses as much as digits as its factorization.

64731409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 64731409 is about 8045.5831982523. The cubic root of 64731409 is about 401.5180006477.

The spelling of 64731409 in words is "sixty-four million, seven hundred thirty-one thousand, four hundred nine".