20535990331 has 4 divisors (see below), whose sum is σ = 21198441664. Its totient is φ = 19873539000.

The previous prime is 20535990323. The next prime is 20535990367. The reversal of 20535990331 is 13309953502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13309953502 = 2 ⋅6654976751.

It is a cyclic number.

It is not a de Polignac number, because 20535990331 - 2³ = 20535990323 is a prime.

It is a super-2 number, since 2×20535990331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20535990131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 331225620 + ... + 331225681.

It is an arithmetic number, because the mean of its divisors is an integer number (5299610416).

Almost surely, 2^20535990331 is an apocalyptic number.

20535990331 is a deficient number, since it is larger than the sum of its proper divisors (662451333).

20535990331 is an equidigital number, since it uses as much as digits as its factorization.

20535990331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662451332.

The product of its (nonzero) digits is 109350, while the sum is 40.

The spelling of 20535990331 in words is "twenty billion, five hundred thirty-five million, nine hundred ninety thousand, three hundred thirty-one".