61565561051 has 4 divisors (see below), whose sum is σ = 61573732704. Its totient is φ = 61557389400.

The previous prime is 61565561041. The next prime is 61565561069. The reversal of 61565561051 is 15016556516.

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

It is a cyclic number.

It is not a de Polignac number, because 61565561051 - 2²² = 61561366747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61565561041) 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, 4074515 + ... + 4089596.

It is an arithmetic number, because the mean of its divisors is an integer number (15393433176).

Almost surely, 2^61565561051 is an apocalyptic number.

61565561051 is a deficient number, since it is larger than the sum of its proper divisors (8171653).

61565561051 is an equidigital number, since it uses as much as digits as its factorization.

61565561051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8171652.

The product of its (nonzero) digits is 135000, while the sum is 41.

The spelling of 61565561051 in words is "sixty-one billion, five hundred sixty-five million, five hundred sixty-one thousand, fifty-one".