21877677 has 12 divisors (see below), whose sum is σ = 31675644. Its totient is φ = 14550720.

The previous prime is 21877673. The next prime is 21877679. The reversal of 21877677 is 77677812.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 8874441 + 13003236 = 2979^2 + 3606^2 .

It is not a de Polignac number, because 21877677 - 2² = 21877673 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21877673) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1513 + ... + 6785.

It is an arithmetic number, because the mean of its divisors is an integer number (2639637).

Almost surely, 2^21877677 is an apocalyptic number.

It is an amenable number.

21877677 is a deficient number, since it is larger than the sum of its proper divisors (9797967).

21877677 is a wasteful number, since it uses less digits than its factorization.

21877677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5740 (or 5737 counting only the distinct ones).

The product of its digits is 230496, while the sum is 45.

The square root of 21877677 is about 4677.3579080502. The cubic root of 21877677 is about 279.6836435514.

The spelling of 21877677 in words is "twenty-one million, eight hundred seventy-seven thousand, six hundred seventy-seven".