21677492 has 6 divisors (see below), whose sum is σ = 37935618. Its totient is φ = 10838744.

The previous prime is 21677443. The next prime is 21677501. The reversal of 21677492 is 29477612.

It can be written as a sum of positive squares in only one way, i.e., 19678096 + 1999396 = 4436^2 + 1414^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2709683 + ... + 2709690.

It is an arithmetic number, because the mean of its divisors is an integer number (6322603).

Almost surely, 2^21677492 is an apocalyptic number.

It is an amenable number.

21677492 is a deficient number, since it is larger than the sum of its proper divisors (16258126).

21677492 is a wasteful number, since it uses less digits than its factorization.

21677492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5419377 (or 5419375 counting only the distinct ones).

The product of its digits is 42336, while the sum is 38.

The square root of 21677492 is about 4655.9093633790. The cubic root of 21677492 is about 278.8279751293.

The spelling of 21677492 in words is "twenty-one million, six hundred seventy-seven thousand, four hundred ninety-two".