55619999 has 4 divisors (see below), whose sum is σ = 57537960. Its totient is φ = 53702040.

The previous prime is 55619969. The next prime is 55620007. The reversal of 55619999 is 99991655.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 55619999 - 2⁸ = 55619743 is a prime.

It is a Duffinian number.

55619999 is a modest number, since divided by 9999 gives 5561 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 55619999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55619969) 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, 958937 + ... + 958994.

It is an arithmetic number, because the mean of its divisors is an integer number (14384490).

Almost surely, 2^55619999 is an apocalyptic number.

55619999 is a deficient number, since it is larger than the sum of its proper divisors (1917961).

55619999 is a wasteful number, since it uses less digits than its factorization.

55619999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1917960.

The product of its digits is 984150, while the sum is 53.

The square root of 55619999 is about 7457.8816697505. The cubic root of 55619999 is about 381.7188958312.

The spelling of 55619999 in words is "fifty-five million, six hundred nineteen thousand, nine hundred ninety-nine".