21649077 has 12 divisors (see below), whose sum is σ = 31322304. Its totient is φ = 14409000.

The previous prime is 21649073. The next prime is 21649079. The reversal of 21649077 is 77094612.

It is a happy number.

21649077 is a `hidden beast` number, since 2 + 1 + 649 + 0 + 7 + 7 = 666.

It is not a de Polignac number, because 21649077 - 2² = 21649073 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21649073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5158 + ... + 8360.

It is an arithmetic number, because the mean of its divisors is an integer number (2610192).

Almost surely, 2^21649077 is an apocalyptic number.

It is an amenable number.

21649077 is a deficient number, since it is larger than the sum of its proper divisors (9673227).

21649077 is a wasteful number, since it uses less digits than its factorization.

21649077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3960 (or 3957 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 21649077 is about 4652.8568643361. The cubic root of 21649077 is about 278.7060920069.

The spelling of 21649077 in words is "twenty-one million, six hundred forty-nine thousand, seventy-seven".