21778205404460 has 12 divisors (see below), whose sum is σ = 45734231349408. Its totient is φ = 8711282161776.

The previous prime is 21778205404451. The next prime is 21778205404589. The reversal of 21778205404460 is 6440450287712.

It is a happy number.

It is a hoax number, since the sum of its digits (50) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21778205404399 and 21778205404408.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 544455135092 + ... + 544455135131.

It is an arithmetic number, because the mean of its divisors is an integer number (3811185945784).

Almost surely, 2^{21778205404460} is an apocalyptic number.

21778205404460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21778205404460 is an abundant number, since it is smaller than the sum of its proper divisors (23956025944948).

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

21778205404460 is a wasteful number, since it uses less digits than its factorization.

21778205404460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1088910270232 (or 1088910270230 counting only the distinct ones).

The product of its (nonzero) digits is 3010560, while the sum is 50.

The spelling of 21778205404460 in words is "twenty-one trillion, seven hundred seventy-eight billion, two hundred five million, four hundred four thousand, four hundred sixty".