66356231 has 4 divisors (see below), whose sum is σ = 66392832. Its totient is φ = 66319632.

The previous prime is 66356221. The next prime is 66356239. The reversal of 66356231 is 13265366.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13265366 = 2 ⋅6632683.

It is a cyclic number.

It is not a de Polignac number, because 66356231 - 2¹⁸ = 66094087 is a prime.

It is a super-2 number, since 2×66356231² = 8806298785050722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66356239) 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, 15431 + ... + 19256.

It is an arithmetic number, because the mean of its divisors is an integer number (16598208).

Almost surely, 2^66356231 is an apocalyptic number.

66356231 is a deficient number, since it is larger than the sum of its proper divisors (36601).

66356231 is a wasteful number, since it uses less digits than its factorization.

66356231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36600.

The product of its digits is 19440, while the sum is 32.

The square root of 66356231 is about 8145.9334026249. The cubic root of 66356231 is about 404.8497761200.

The spelling of 66356231 in words is "sixty-six million, three hundred fifty-six thousand, two hundred thirty-one".