21990919639245 has 16 divisors (see below), whose sum is σ = 35185555980672. Its totient is φ = 11728462288320.

The previous prime is 21990919639211. The next prime is 21990919639259. The reversal of 21990919639245 is 54293691909912.

It is not a de Polignac number, because 21990919639245 - 2²⁸ = 21990651203789 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21990919639245.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5710479 + ... + 8751651.

It is an arithmetic number, because the mean of its divisors is an integer number (2199097248792).

Almost surely, 2^{21990919639245} is an apocalyptic number.

It is an amenable number.

21990919639245 is a deficient number, since it is larger than the sum of its proper divisors (13194636341427).

21990919639245 is a wasteful number, since it uses less digits than its factorization.

21990919639245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3523252.

The product of its (nonzero) digits is 85030560, while the sum is 69.

The spelling of 21990919639245 in words is "twenty-one trillion, nine hundred ninety billion, nine hundred nineteen million, six hundred thirty-nine thousand, two hundred forty-five".