55551101010021 has 6 divisors (see below), whose sum is σ = 80240479236710. Its totient is φ = 37034067340008.

The previous prime is 55551101010019. The next prime is 55551101010029. The reversal of 55551101010021 is 12001010115555.

It is a happy number.

55551101010021 is a `hidden beast` number, since 5 + 5 + 551 + 1 + 0 + 1 + 0 + 100 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 55550413836225 + 687173796 = 7453215^2 + 26214^2 .

It is not a de Polignac number, because 55551101010021 - 2¹ = 55551101010019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55551101010029) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3086172278326 + ... + 3086172278343.

Almost surely, 2^{55551101010021} is an apocalyptic number.

It is an amenable number.

55551101010021 is a deficient number, since it is larger than the sum of its proper divisors (24689378226689).

55551101010021 is a wasteful number, since it uses less digits than its factorization.

55551101010021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6172344556675 (or 6172344556672 counting only the distinct ones).

The product of its (nonzero) digits is 1250, while the sum is 27.

Adding to 55551101010021 its reverse (12001010115555), we get a palindrome (67552111125576).

The spelling of 55551101010021 in words is "fifty-five trillion, five hundred fifty-one billion, one hundred one million, ten thousand, twenty-one".