21407444731 has 8 divisors (see below), whose sum is σ = 21491324928. Its totient is φ = 21323601000.

The previous prime is 21407444671. The next prime is 21407444753. The reversal of 21407444731 is 13744470412.

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

It is a cyclic number.

It is not a de Polignac number, because 21407444731 - 2¹⁷ = 21407313659 is a prime.

It is a super-2 number, since 2×21407444731² (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 (21407444791) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2079126 + ... + 2089396.

It is an arithmetic number, because the mean of its divisors is an integer number (2686415616).

Almost surely, 2^21407444731 is an apocalyptic number.

21407444731 is a deficient number, since it is larger than the sum of its proper divisors (83880197).

21407444731 is a wasteful number, since it uses less digits than its factorization.

21407444731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18233.

The product of its (nonzero) digits is 75264, while the sum is 37.

The spelling of 21407444731 in words is "twenty-one billion, four hundred seven million, four hundred forty-four thousand, seven hundred thirty-one".