42561633251 has 4 divisors (see below), whose sum is σ = 42564714192. Its totient is φ = 42558552312.

The previous prime is 42561633223. The next prime is 42561633287. The reversal of 42561633251 is 15233616524.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42561633251 is a prime.

It is a super-2 number, since 2×42561633251² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42561636251) 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, 1519655 + ... + 1547408.

It is an arithmetic number, because the mean of its divisors is an integer number (10641178548).

Almost surely, 2^42561633251 is an apocalyptic number.

42561633251 is a deficient number, since it is larger than the sum of its proper divisors (3080941).

42561633251 is a wasteful number, since it uses less digits than its factorization.

42561633251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3080940.

The product of its digits is 129600, while the sum is 38.

The spelling of 42561633251 in words is "forty-two billion, five hundred sixty-one million, six hundred thirty-three thousand, two hundred fifty-one".