55122117961 has 3 divisors (see below), whose sum is σ = 55122352743. Its totient is φ = 55121883180.

The previous prime is 55122117943. The next prime is 55122117977. The reversal of 55122117961 is 16971122155.

The square root of 55122117961 is 234781.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 8699106361 + 46423011600 = 93269^2 + 215460^2 .

It is not a de Polignac number, because 55122117961 - 2¹³ = 55122109769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55122117901) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 117391 + ... + 352171.

It is an arithmetic number, because the mean of its divisors is an integer number (18374117581).

Almost surely, 2^55122117961 is an apocalyptic number.

55122117961 is the 234781-st square number.

55122117961 is the 117391-st centered octagonal number.

It is an amenable number.

55122117961 is a deficient number, since it is larger than the sum of its proper divisors (234782).

55122117961 is an frugal number, since it uses more digits than its factorization.

55122117961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469562 (or 234781 counting only the distinct ones).

The product of its digits is 37800, while the sum is 40.

The spelling of 55122117961 in words is "fifty-five billion, one hundred twenty-two million, one hundred seventeen thousand, nine hundred sixty-one".