55521245421 has 32 divisors (see below), whose sum is σ = 87110553600. Its totient is φ = 34829498880.

The previous prime is 55521245413. The next prime is 55521245443. The reversal of 55521245421 is 12454212555.

55521245421 is a `hidden beast` number, since 55 + 52 + 12 + 4 + 542 + 1 = 666.

It is not a de Polignac number, because 55521245421 - 2³ = 55521245413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55521245821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2868745 + ... + 2888033.

It is an arithmetic number, because the mean of its divisors is an integer number (2722204800).

Almost surely, 2^55521245421 is an apocalyptic number.

55521245421 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

55521245421 is a deficient number, since it is larger than the sum of its proper divisors (31589308179).

55521245421 is a wasteful number, since it uses less digits than its factorization.

55521245421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25586 (or 25580 counting only the distinct ones).

The product of its digits is 80000, while the sum is 36.

Adding to 55521245421 its reverse (12454212555), we get a palindrome (67975457976).

The spelling of 55521245421 in words is "fifty-five billion, five hundred twenty-one million, two hundred forty-five thousand, four hundred twenty-one".