55904101621 has 2 divisors, whose sum is σ = 55904101622. Its totient is φ = 55904101620.

The previous prime is 55904101613. The next prime is 55904101667. The reversal of 55904101621 is 12610140955.

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., 35257572900 + 20646528721 = 187770^2 + 143689^2 .

It is a cyclic number.

It is not a de Polignac number, because 55904101621 - 2³ = 55904101613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55904501621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27952050810 + 27952050811.

It is an arithmetic number, because the mean of its divisors is an integer number (27952050811).

Almost surely, 2^55904101621 is an apocalyptic number.

It is an amenable number.

55904101621 is a deficient number, since it is larger than the sum of its proper divisors (1).

55904101621 is an equidigital number, since it uses as much as digits as its factorization.

55904101621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10800, while the sum is 34.

The spelling of 55904101621 in words is "fifty-five billion, nine hundred four million, one hundred one thousand, six hundred twenty-one".