55115213 has 2 divisors, whose sum is σ = 55115214. Its totient is φ = 55115212.

The previous prime is 55115209. The next prime is 55115227. The reversal of 55115213 is 31251155.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47375689 + 7739524 = 6883^2 + 2782^2 .

It is a cyclic number.

It is not a de Polignac number, because 55115213 - 2² = 55115209 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55115233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27557606 + 27557607.

It is an arithmetic number, because the mean of its divisors is an integer number (27557607).

Almost surely, 2^55115213 is an apocalyptic number.

It is an amenable number.

55115213 is a deficient number, since it is larger than the sum of its proper divisors (1).

55115213 is an equidigital number, since it uses as much as digits as its factorization.

55115213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 750, while the sum is 23.

The square root of 55115213 is about 7423.9620823385. The cubic root of 55115213 is about 380.5606060609.

Adding to 55115213 its reverse (31251155), we get a palindrome (86366368).

The spelling of 55115213 in words is "fifty-five million, one hundred fifteen thousand, two hundred thirteen".