55415561 has 4 divisors (see below), whose sum is σ = 55852032. Its totient is φ = 54979092.

The previous prime is 55415557. The next prime is 55415567. The reversal of 55415561 is 16551455.

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 a cyclic number.

It is not a de Polignac number, because 55415561 - 2² = 55415557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55415567) 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, 218045 + ... + 218298.

It is an arithmetic number, because the mean of its divisors is an integer number (13963008).

Almost surely, 2^55415561 is an apocalyptic number.

It is an amenable number.

55415561 is a deficient number, since it is larger than the sum of its proper divisors (436471).

55415561 is a wasteful number, since it uses less digits than its factorization.

55415561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436470.

The product of its digits is 15000, while the sum is 32.

The square root of 55415561 is about 7444.1628810767. The cubic root of 55415561 is about 381.2506370678.

The spelling of 55415561 in words is "fifty-five million, four hundred fifteen thousand, five hundred sixty-one".