21777468 has 24 divisors (see below), whose sum is σ = 51123072. Its totient is φ = 7215024.

The previous prime is 21777467. The next prime is 21777487. The reversal of 21777468 is 86477712.

It is a super-2 number, since 2×21777468² = 948516224982048, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21777461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3430 + ... + 7437.

It is an arithmetic number, because the mean of its divisors is an integer number (2130128).

Almost surely, 2^21777468 is an apocalyptic number.

It is an amenable number.

21777468 is an abundant number, since it is smaller than the sum of its proper divisors (29345604).

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

21777468 is a wasteful number, since it uses less digits than its factorization.

21777468 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11041 (or 11039 counting only the distinct ones).

The product of its digits is 131712, while the sum is 42.

The square root of 21777468 is about 4666.6334760724. The cubic root of 21777468 is about 279.2559668376.

The spelling of 21777468 in words is "twenty-one million, seven hundred seventy-seven thousand, four hundred sixty-eight".