55562021 has 2 divisors, whose sum is σ = 55562022. Its totient is φ = 55562020.

The previous prime is 55561993. The next prime is 55562029. The reversal of 55562021 is 12026555.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33189121 + 22372900 = 5761^2 + 4730^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55562021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55562029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27781010 + 27781011.

It is an arithmetic number, because the mean of its divisors is an integer number (27781011).

Almost surely, 2^55562021 is an apocalyptic number.

It is an amenable number.

55562021 is a deficient number, since it is larger than the sum of its proper divisors (1).

55562021 is an equidigital number, since it uses as much as digits as its factorization.

55562021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 55562021 is about 7453.9936275798. The cubic root of 55562021 is about 381.5862157829.

Adding to 55562021 its reverse (12026555), we get a palindrome (67588576).

The spelling of 55562021 in words is "fifty-five million, five hundred sixty-two thousand, twenty-one".