64609693 has 4 divisors (see below), whose sum is σ = 66112288. Its totient is φ = 63107100.

The previous prime is 64609669. The next prime is 64609697. The reversal of 64609693 is 39690646.

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 64609693 - 2¹⁷ = 64478621 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 1502551 = 64609693 / (6 + 4 + 6 + 0 + 9 + 6 + 9 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64609697) 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, 751233 + ... + 751318.

It is an arithmetic number, because the mean of its divisors is an integer number (16528072).

Almost surely, 2^64609693 is an apocalyptic number.

64609693 is the 4297-th centered heptagonal number.

It is an amenable number.

64609693 is a deficient number, since it is larger than the sum of its proper divisors (1502595).

64609693 is a wasteful number, since it uses less digits than its factorization.

64609693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1502594.

The product of its (nonzero) digits is 209952, while the sum is 43.

The square root of 64609693 is about 8038.0154889127. The cubic root of 64609693 is about 401.2661814820.

The spelling of 64609693 in words is "sixty-four million, six hundred nine thousand, six hundred ninety-three".