64381913 has 2 divisors, whose sum is σ = 64381914. Its totient is φ = 64381912.

The previous prime is 64381871. The next prime is 64381927. The reversal of 64381913 is 31918346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62047129 + 2334784 = 7877^2 + 1528^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64381913 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (64381973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32190956 + 32190957.

It is an arithmetic number, because the mean of its divisors is an integer number (32190957).

Almost surely, 2^64381913 is an apocalyptic number.

It is an amenable number.

64381913 is a deficient number, since it is larger than the sum of its proper divisors (1).

64381913 is an equidigital number, since it uses as much as digits as its factorization.

64381913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 35.

The square root of 64381913 is about 8023.8340586032. The cubic root of 64381913 is about 400.7940746538.

The spelling of 64381913 in words is "sixty-four million, three hundred eighty-one thousand, nine hundred thirteen".