21431795 has 16 divisors (see below), whose sum is σ = 32064768. Its totient is φ = 13359840.

The previous prime is 21431777. The next prime is 21431821. The reversal of 21431795 is 59713412.

It is not a de Polignac number, because 21431795 - 2¹⁰ = 21430771 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27449 + ... + 28218.

It is an arithmetic number, because the mean of its divisors is an integer number (2004048).

Almost surely, 2^21431795 is an apocalyptic number.

21431795 is a deficient number, since it is larger than the sum of its proper divisors (10632973).

21431795 is a wasteful number, since it uses less digits than its factorization.

21431795 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55690.

The product of its digits is 7560, while the sum is 32.

The square root of 21431795 is about 4629.4486712783. The cubic root of 21431795 is about 277.7705393966.

It can be divided in two parts, 214317 and 95, that added together give a palindrome (214412).

The spelling of 21431795 in words is "twenty-one million, four hundred thirty-one thousand, seven hundred ninety-five".