21401746494 has 16 divisors (see below), whose sum is σ = 43528976640. Its totient is φ = 7013001560.

The previous prime is 21401746493. The next prime is 21401746543. The reversal of 21401746494 is 49464710412.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21401746493) 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, 30228102 + ... + 30228809.

It is an arithmetic number, because the mean of its divisors is an integer number (2720561040).

Almost surely, 2^21401746494 is an apocalyptic number.

21401746494 is an abundant number, since it is smaller than the sum of its proper divisors (22127230146).

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

21401746494 is a wasteful number, since it uses less digits than its factorization.

21401746494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60456975.

The product of its (nonzero) digits is 193536, while the sum is 42.

The spelling of 21401746494 in words is "twenty-one billion, four hundred one million, seven hundred forty-six thousand, four hundred ninety-four".