61111655066561 has 4 divisors (see below), whose sum is σ = 66667260072624. Its totient is φ = 55556050060500.

The previous prime is 61111655066507. The next prime is 61111655066569. The reversal of 61111655066561 is 16566055611116.

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 61111655066561 - 2²⁶ = 61111587957697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61111655066569) 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, 2777802503015 + ... + 2777802503036.

It is an arithmetic number, because the mean of its divisors is an integer number (16666815018156).

Almost surely, 2^{61111655066561} is an apocalyptic number.

It is an amenable number.

61111655066561 is a deficient number, since it is larger than the sum of its proper divisors (5555605006063).

61111655066561 is a wasteful number, since it uses less digits than its factorization.

61111655066561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5555605006062.

The product of its (nonzero) digits is 972000, while the sum is 50.

The spelling of 61111655066561 in words is "sixty-one trillion, one hundred eleven billion, six hundred fifty-five million, sixty-six thousand, five hundred sixty-one".