21777823249 has 16 divisors (see below), whose sum is σ = 26808221440. Its totient is φ = 17227753920.

The previous prime is 21777823213. The next prime is 21777823283. The reversal of 21777823249 is 94232877712.

It is not a de Polignac number, because 21777823249 - 2¹¹ = 21777821201 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21777823196 and 21777823205.

It is not an unprimeable number, because it can be changed into a prime (21777823289) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 592684 + ... + 628354.

It is an arithmetic number, because the mean of its divisors is an integer number (1675513840).

Almost surely, 2^21777823249 is an apocalyptic number.

It is an amenable number.

21777823249 is a deficient number, since it is larger than the sum of its proper divisors (5030398191).

21777823249 is a wasteful number, since it uses less digits than its factorization.

21777823249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42400.

The product of its digits is 2370816, while the sum is 52.

The spelling of 21777823249 in words is "twenty-one billion, seven hundred seventy-seven million, eight hundred twenty-three thousand, two hundred forty-nine".