21629715 has 8 divisors (see below), whose sum is σ = 34607568. Its totient is φ = 11535840.

The previous prime is 21629689. The next prime is 21629743. The reversal of 21629715 is 51792612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21629715 - 2⁹ = 21629203 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 720976 + ... + 721005.

It is an arithmetic number, because the mean of its divisors is an integer number (4325946).

Almost surely, 2^21629715 is an apocalyptic number.

21629715 is a deficient number, since it is larger than the sum of its proper divisors (12977853).

21629715 is a wasteful number, since it uses less digits than its factorization.

21629715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1441989.

The product of its digits is 7560, while the sum is 33.

The square root of 21629715 is about 4650.7757417446. The cubic root of 21629715 is about 278.6229796585.

The spelling of 21629715 in words is "twenty-one million, six hundred twenty-nine thousand, seven hundred fifteen".