55207681 has 2 divisors, whose sum is σ = 55207682. Its totient is φ = 55207680.

The previous prime is 55207639. The next prime is 55207697. The reversal of 55207681 is 18670255.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31539456 + 23668225 = 5616^2 + 4865^2 .

It is a cyclic number.

It is not a de Polignac number, because 55207681 - 2⁹ = 55207169 is a prime.

It is a super-2 number, since 2×55207681² = 6095776082795522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (55207631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27603840 + 27603841.

It is an arithmetic number, because the mean of its divisors is an integer number (27603841).

Almost surely, 2^55207681 is an apocalyptic number.

It is an amenable number.

55207681 is a deficient number, since it is larger than the sum of its proper divisors (1).

55207681 is an equidigital number, since it uses as much as digits as its factorization.

55207681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16800, while the sum is 34.

The square root of 55207681 is about 7430.1871443457. The cubic root of 55207681 is about 380.7733121060.

The spelling of 55207681 in words is "fifty-five million, two hundred seven thousand, six hundred eighty-one".