21460344738 has 16 divisors (see below), whose sum is σ = 49052216640. Its totient is φ = 6131527056.

The previous prime is 21460344679. The next prime is 21460344749. The reversal of 21460344738 is 83744306412.

It is a Harshad number since it is a multiple of its sum of digits (42), and also a Moran number because the ratio is a prime number: 510960589 = 21460344738 / (2 + 1 + 4 + 6 + 0 + 3 + 4 + 4 + 7 + 3 + 8).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21460344738.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 255480253 + ... + 255480336.

It is an arithmetic number, because the mean of its divisors is an integer number (3065763540).

Almost surely, 2^21460344738 is an apocalyptic number.

21460344738 is an abundant number, since it is smaller than the sum of its proper divisors (27591871902).

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

21460344738 is a wasteful number, since it uses less digits than its factorization.

21460344738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 510960601.

The product of its (nonzero) digits is 387072, while the sum is 42.

The spelling of 21460344738 in words is "twenty-one billion, four hundred sixty million, three hundred forty-four thousand, seven hundred thirty-eight".