55699309 has 2 divisors, whose sum is σ = 55699310. Its totient is φ = 55699308.

The previous prime is 55699297. The next prime is 55699313. The reversal of 55699309 is 90399655.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55547209 + 152100 = 7453^2 + 390^2 .

It is a cyclic number.

It is not a de Polignac number, because 55699309 - 2¹¹ = 55697261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55699909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27849654 + 27849655.

It is an arithmetic number, because the mean of its divisors is an integer number (27849655).

Almost surely, 2^55699309 is an apocalyptic number.

It is an amenable number.

55699309 is a deficient number, since it is larger than the sum of its proper divisors (1).

55699309 is an equidigital number, since it uses as much as digits as its factorization.

55699309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 328050, while the sum is 46.

The square root of 55699309 is about 7463.1969691279. The cubic root of 55699309 is about 381.9002439554.

It can be divided in two parts, 5569 and 9309, that added together give a triangular number (14878 = T₁₇₂).

The spelling of 55699309 in words is "fifty-five million, six hundred ninety-nine thousand, three hundred nine".