21439950408 has 96 divisors (see below), whose sum is σ = 58345255800. Its totient is φ = 7112448000.

The previous prime is 21439950397. The next prime is 21439950409. The reversal of 21439950408 is 80405993412.

21439950408 is a `hidden beast` number, since 214 + 399 + 5 + 0 + 40 + 8 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 13642707204 + 7797243204 = 116802^2 + 88302^2 .

It is not an unprimeable number, because it can be changed into a prime (21439950409) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21248208 + ... + 21249216.

Almost surely, 2^21439950408 is an apocalyptic number.

It is an amenable number.

21439950408 is an abundant number, since it is smaller than the sum of its proper divisors (36905305392).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21439950408 is a wasteful number, since it uses less digits than its factorization.

21439950408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2143 (or 2136 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 21439950408 in words is "twenty-one billion, four hundred thirty-nine million, nine hundred fifty thousand, four hundred eight".