20009984531 has 4 divisors (see below), whose sum is σ = 20012257200. Its totient is φ = 20007711864.

The previous prime is 20009984503. The next prime is 20009984551. The reversal of 20009984531 is 13548990002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20009984531 - 2¹⁰ = 20009983507 is a prime.

It is a super-2 number, since 2×20009984531² (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 (20009984551) 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, 1123076 + ... + 1140753.

It is an arithmetic number, because the mean of its divisors is an integer number (5003064300).

Almost surely, 2^20009984531 is an apocalyptic number.

20009984531 is a deficient number, since it is larger than the sum of its proper divisors (2272669).

20009984531 is an equidigital number, since it uses as much as digits as its factorization.

20009984531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2272668.

The product of its (nonzero) digits is 77760, while the sum is 41.

The spelling of 20009984531 in words is "twenty billion, nine million, nine hundred eighty-four thousand, five hundred thirty-one".