42647668521 has 4 divisors (see below), whose sum is σ = 56863558032. Its totient is φ = 28431779012.

The previous prime is 42647668513. The next prime is 42647668559. The reversal of 42647668521 is 12586674624.

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 42647668521 - 2³ = 42647668513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (42647668561) 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, 7107944751 + ... + 7107944756.

It is an arithmetic number, because the mean of its divisors is an integer number (14215889508).

Almost surely, 2^42647668521 is an apocalyptic number.

It is an amenable number.

42647668521 is a deficient number, since it is larger than the sum of its proper divisors (14215889511).

42647668521 is a wasteful number, since it uses less digits than its factorization.

42647668521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14215889510.

The product of its digits is 3870720, while the sum is 51.

The spelling of 42647668521 in words is "forty-two billion, six hundred forty-seven million, six hundred sixty-eight thousand, five hundred twenty-one".