66570681 has 4 divisors (see below), whose sum is σ = 88760912. Its totient is φ = 44380452.

The previous prime is 66570649. The next prime is 66570683. The reversal of 66570681 is 18607566.

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 not a de Polignac number, because 66570681 - 2⁵ = 66570649 is a prime.

It is a super-2 number, since 2×66570681² = 8863311137607522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66570683) 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, 11095111 + ... + 11095116.

It is an arithmetic number, because the mean of its divisors is an integer number (22190228).

Almost surely, 2^66570681 is an apocalyptic number.

It is an amenable number.

66570681 is a deficient number, since it is larger than the sum of its proper divisors (22190231).

66570681 is a wasteful number, since it uses less digits than its factorization.

66570681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22190230.

The product of its (nonzero) digits is 60480, while the sum is 39.

The square root of 66570681 is about 8159.0857943767. The cubic root of 66570681 is about 405.2854381643.

The spelling of 66570681 in words is "sixty-six million, five hundred seventy thousand, six hundred eighty-one".