21120694768446 has 128 divisors (see below), whose sum is σ = 53672606539776. Its totient is φ = 5389990871040.

The previous prime is 21120694768421. The next prime is 21120694768463. The reversal of 21120694768446 is 64486749602112.

It is a self number, because there is not a number n which added to its sum of digits gives 21120694768446.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 158648566 + ... + 158781638.

It is an arithmetic number, because the mean of its divisors is an integer number (419317238592).

Almost surely, 2^{21120694768446} is an apocalyptic number.

21120694768446 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21120694768446, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26836303269888).

21120694768446 is an abundant number, since it is smaller than the sum of its proper divisors (32551911771330).

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

21120694768446 is a wasteful number, since it uses less digits than its factorization.

21120694768446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142506.

The product of its (nonzero) digits is 27869184, while the sum is 60.

The spelling of 21120694768446 in words is "twenty-one trillion, one hundred twenty billion, six hundred ninety-four million, seven hundred sixty-eight thousand, four hundred forty-six".