55121779 has 8 divisors (see below), whose sum is σ = 57357360. Its totient is φ = 52908576.

The previous prime is 55121767. The next prime is 55121819. The reversal of 55121779 is 97712155.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 55121779 - 2⁵ = 55121747 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55121719) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 477 + ... + 10510.

It is an arithmetic number, because the mean of its divisors is an integer number (7169670).

Almost surely, 2^55121779 is an apocalyptic number.

55121779 is a deficient number, since it is larger than the sum of its proper divisors (2235581).

55121779 is a wasteful number, since it uses less digits than its factorization.

55121779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11189.

The product of its digits is 22050, while the sum is 37.

The square root of 55121779 is about 7424.4042858670. The cubic root of 55121779 is about 380.5757178094.

The spelling of 55121779 in words is "fifty-five million, one hundred twenty-one thousand, seven hundred seventy-nine".