21429655 has 8 divisors (see below), whose sum is σ = 27693792. Its totient is φ = 15824928.

The previous prime is 21429643. The next prime is 21429671. The reversal of 21429655 is 55692412.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21429655 - 2¹⁵ = 21396887 is a prime.

It is a super-2 number, since 2×21429655² = 918460226838050, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21429655.

It is a congruent number.

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, 164779 + ... + 164908.

It is an arithmetic number, because the mean of its divisors is an integer number (3461724).

Almost surely, 2^21429655 is an apocalyptic number.

21429655 is a deficient number, since it is larger than the sum of its proper divisors (6264137).

21429655 is a wasteful number, since it uses less digits than its factorization.

21429655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329705.

The product of its digits is 21600, while the sum is 34.

The square root of 21429655 is about 4629.2175364742. The cubic root of 21429655 is about 277.7612938070.

The spelling of 21429655 in words is "twenty-one million, four hundred twenty-nine thousand, six hundred fifty-five".