20031555213 has 6 divisors (see below), whose sum is σ = 28934468654. Its totient is φ = 13354370136.

The previous prime is 20031555199. The next prime is 20031555223. The reversal of 20031555213 is 31255513002.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 14496641604 + 5534913609 = 120402^2 + 74397^2 .

It is not a de Polignac number, because 20031555213 - 2⁸ = 20031554957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20031555223) 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, 1112864170 + ... + 1112864187.

Almost surely, 2^20031555213 is an apocalyptic number.

It is an amenable number.

20031555213 is a deficient number, since it is larger than the sum of its proper divisors (8902913441).

20031555213 is a wasteful number, since it uses less digits than its factorization.

20031555213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2225728363 (or 2225728360 counting only the distinct ones).

The product of its (nonzero) digits is 4500, while the sum is 27.

The spelling of 20031555213 in words is "twenty billion, thirty-one million, five hundred fifty-five thousand, two hundred thirteen".