21777488890073 has 6 divisors (see below), whose sum is σ = 25332997280346. Its totient is φ = 18666419048592.

The previous prime is 21777488890049. The next prime is 21777488890099. The reversal of 21777488890073 is 37009888477712.

It can be written as a sum of positive squares in only one way, i.e., 21513613528729 + 263875361344 = 4638277^2 + 513688^2 .

It is not a de Polignac number, because 21777488890073 - 2²⁴ = 21777472112857 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21777488889979 and 21777488890006.

It is not an unprimeable number, because it can be changed into a prime (21777488890873) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 222219274340 + ... + 222219274437.

It is an arithmetic number, because the mean of its divisors is an integer number (4222166213391).

Almost surely, 2^{21777488890073} is an apocalyptic number.

It is an amenable number.

21777488890073 is a deficient number, since it is larger than the sum of its proper divisors (3555508390273).

21777488890073 is an equidigital number, since it uses as much as digits as its factorization.

21777488890073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444438548791 (or 444438548784 counting only the distinct ones).

The product of its (nonzero) digits is 265531392, while the sum is 71.

The spelling of 21777488890073 in words is "twenty-one trillion, seven hundred seventy-seven billion, four hundred eighty-eight million, eight hundred ninety thousand, seventy-three".