21758419490 has 16 divisors (see below), whose sum is σ = 39237558840. Its totient is φ = 8687278080.

The previous prime is 21758419481. The next prime is 21758419511. The reversal of 21758419490 is 9491485712.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 17458601161 + 4299818329 = 132131^2 + 65573^2 .

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 7 ways as a sum of consecutive naturals, for example, 2005535 + ... + 2016354.

Almost surely, 2^21758419490 is an apocalyptic number.

21758419490 is a deficient number, since it is larger than the sum of its proper divisors (17479139350).

21758419490 is a wasteful number, since it uses less digits than its factorization.

21758419490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4022437.

The product of its (nonzero) digits is 725760, while the sum is 50.

The spelling of 21758419490 in words is "twenty-one billion, seven hundred fifty-eight million, four hundred nineteen thousand, four hundred ninety".