64649641 has 4 divisors (see below), whose sum is σ = 73885312. Its totient is φ = 55413972.

The previous prime is 64649639. The next prime is 64649653. The reversal of 64649641 is 14694646.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64649641 - 2¹ = 64649639 is a prime.

It is the 8041-st Hogben number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64649594 and 64649603.

It is not an unprimeable number, because it can be changed into a prime (64649041) by changing a digit.

It is a nontrivial repunit in base 8040.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4617825 + ... + 4617838.

It is an arithmetic number, because the mean of its divisors is an integer number (18471328).

Almost surely, 2^64649641 is an apocalyptic number.

It is an amenable number.

64649641 is a deficient number, since it is larger than the sum of its proper divisors (9235671).

64649641 is an equidigital number, since it uses as much as digits as its factorization.

64649641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9235670.

The product of its digits is 124416, while the sum is 40.

The square root of 64649641 is about 8040.5000466389. The cubic root of 64649641 is about 401.3488650449.

The spelling of 64649641 in words is "sixty-four million, six hundred forty-nine thousand, six hundred forty-one".