55158409 has 4 divisors (see below), whose sum is σ = 55935360. Its totient is φ = 54381460.

The previous prime is 55158359. The next prime is 55158413. The reversal of 55158409 is 90485155.

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 55158409 - 2⁷ = 55158281 is a prime.

It is a super-2 number, since 2×55158409² = 6084900166822562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55158479) 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, 388369 + ... + 388510.

It is an arithmetic number, because the mean of its divisors is an integer number (13983840).

Almost surely, 2^55158409 is an apocalyptic number.

It is an amenable number.

55158409 is a deficient number, since it is larger than the sum of its proper divisors (776951).

55158409 is an equidigital number, since it uses as much as digits as its factorization.

55158409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 776950.

The product of its (nonzero) digits is 36000, while the sum is 37.

The square root of 55158409 is about 7426.8707407629. The cubic root of 55158409 is about 380.6600002956.

It can be divided in two parts, 5515 and 8409, that added together give a square (13924 = 118²).

The spelling of 55158409 in words is "fifty-five million, one hundred fifty-eight thousand, four hundred nine".