21527668 has 6 divisors (see below), whose sum is σ = 37673426. Its totient is φ = 10763832.

The previous prime is 21527659. The next prime is 21527677. The reversal of 21527668 is 86672512.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21527659) and next prime (21527677).

It can be written as a sum of positive squares in only one way, i.e., 20322064 + 1205604 = 4508^2 + 1098^2 .

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, 2690955 + ... + 2690962.

Almost surely, 2^21527668 is an apocalyptic number.

It is an amenable number.

21527668 is a deficient number, since it is larger than the sum of its proper divisors (16145758).

21527668 is a wasteful number, since it uses less digits than its factorization.

21527668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5381921 (or 5381919 counting only the distinct ones).

The product of its digits is 40320, while the sum is 37.

The square root of 21527668 is about 4639.7918056740. The cubic root of 21527668 is about 278.1841162559.

The spelling of 21527668 in words is "twenty-one million, five hundred twenty-seven thousand, six hundred sixty-eight".