21431204018 has 8 divisors (see below), whose sum is σ = 36739206912. Its totient is φ = 9184801716.

The previous prime is 21431204009. The next prime is 21431204023. The reversal of 21431204018 is 81040213412.

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

It is a super-2 number, since 2×21431204018² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 765400130 + ... + 765400157.

It is an arithmetic number, because the mean of its divisors is an integer number (4592400864).

Almost surely, 2^21431204018 is an apocalyptic number.

21431204018 is a deficient number, since it is larger than the sum of its proper divisors (15308002894).

21431204018 is a wasteful number, since it uses less digits than its factorization.

21431204018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1530800296.

The product of its (nonzero) digits is 1536, while the sum is 26.

The spelling of 21431204018 in words is "twenty-one billion, four hundred thirty-one million, two hundred four thousand, eighteen".