64727391 has 16 divisors (see below), whose sum is σ = 89532000. Its totient is φ = 41545728.

The previous prime is 64727387. The next prime is 64727407. The reversal of 64727391 is 19372746.

It is not a de Polignac number, because 64727391 - 2² = 64727387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64727321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38235 + ... + 39891.

It is an arithmetic number, because the mean of its divisors is an integer number (5595750).

Almost surely, 2^64727391 is an apocalyptic number.

64727391 is a deficient number, since it is larger than the sum of its proper divisors (24804609).

64727391 is a wasteful number, since it uses less digits than its factorization.

64727391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2138.

The product of its digits is 63504, while the sum is 39.

The square root of 64727391 is about 8045.3334921556. Note that the first 3 decimals coincide. The cubic root of 64727391 is about 401.5096928172.

The spelling of 64727391 in words is "sixty-four million, seven hundred twenty-seven thousand, three hundred ninety-one".