20531815954 has 8 divisors (see below), whose sum is σ = 33166779660. Its totient is φ = 9476222736.

The previous prime is 20531815949. The next prime is 20531815961. The reversal of 20531815954 is 45951813502.

It can be written as a sum of positive squares in 2 ways, for example, as 18740241025 + 1791574929 = 136895^2 + 42327^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 20531815954.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 394842589 + ... + 394842640.

Almost surely, 2^20531815954 is an apocalyptic number.

20531815954 is a deficient number, since it is larger than the sum of its proper divisors (12634963706).

20531815954 is a wasteful number, since it uses less digits than its factorization.

20531815954 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 789685244.

The product of its (nonzero) digits is 216000, while the sum is 43.

The spelling of 20531815954 in words is "twenty billion, five hundred thirty-one million, eight hundred fifteen thousand, nine hundred fifty-four".