20551055551 has 24 divisors (see below), whose sum is σ = 22463170944. Its totient is φ = 18792259200.

The previous prime is 20551055513. The next prime is 20551055573. The reversal of 20551055551 is 15555015502.

20551055551 = 49² + 50² + ... + 3950².

It is not a de Polignac number, because 20551055551 - 2⁷ = 20551055423 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 (20551055351) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10532626 + ... + 10534576.

It is an arithmetic number, because the mean of its divisors is an integer number (935965456).

Almost surely, 2^20551055551 is an apocalyptic number.

20551055551 is a deficient number, since it is larger than the sum of its proper divisors (1912115393).

20551055551 is a wasteful number, since it uses less digits than its factorization.

20551055551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2531 (or 2518 counting only the distinct ones).

The product of its (nonzero) digits is 31250, while the sum is 34.

The spelling of 20551055551 in words is "twenty billion, five hundred fifty-one million, fifty-five thousand, five hundred fifty-one".