55615511 has 4 divisors (see below), whose sum is σ = 63560592. Its totient is φ = 47670432.

The previous prime is 55615493. The next prime is 55615513. The reversal of 55615511 is 11551655.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11551655 = 5 ⋅2310331.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55615511 is a prime.

It is a super-2 number, since 2×55615511² = 6186170127582242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55615513) 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, 3972530 + ... + 3972543.

It is an arithmetic number, because the mean of its divisors is an integer number (15890148).

Almost surely, 2^55615511 is an apocalyptic number.

55615511 is a deficient number, since it is larger than the sum of its proper divisors (7945081).

55615511 is an equidigital number, since it uses as much as digits as its factorization.

55615511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7945080.

The product of its digits is 3750, while the sum is 29.

The square root of 55615511 is about 7457.5807739508. The cubic root of 55615511 is about 381.7086285381.

The spelling of 55615511 in words is "fifty-five million, six hundred fifteen thousand, five hundred eleven".