64640453 has 4 divisors (see below), whose sum is σ = 64667040. Its totient is φ = 64613868.

The previous prime is 64640437. The next prime is 64640473. The reversal of 64640453 is 35404646.

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 64640453 - 2⁴ = 64640437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64640473) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9233 + ... + 14646.

It is an arithmetic number, because the mean of its divisors is an integer number (16166760).

Almost surely, 2^64640453 is an apocalyptic number.

It is an amenable number.

64640453 is a deficient number, since it is larger than the sum of its proper divisors (26587).

64640453 is a wasteful number, since it uses less digits than its factorization.

64640453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26586.

The product of its (nonzero) digits is 34560, while the sum is 32.

The square root of 64640453 is about 8039.9286688378. The cubic root of 64640453 is about 401.3298509249.

The spelling of 64640453 in words is "sixty-four million, six hundred forty thousand, four hundred fifty-three".