21696155 has 8 divisors (see below), whose sum is σ = 28038192. Its totient is φ = 16021728.

The previous prime is 21696149. The next prime is 21696161. The reversal of 21696155 is 55169612.

It is an interprime number because it is at equal distance from previous prime (21696149) and next prime (21696161).

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 21696155 - 2¹⁶ = 21630619 is a prime.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 166829 + ... + 166958.

It is an arithmetic number, because the mean of its divisors is an integer number (3504774).

Almost surely, 2^21696155 is an apocalyptic number.

21696155 is a deficient number, since it is larger than the sum of its proper divisors (6342037).

21696155 is a wasteful number, since it uses less digits than its factorization.

21696155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333805.

The product of its digits is 16200, while the sum is 35.

The square root of 21696155 is about 4657.9131593451. The cubic root of 21696155 is about 278.9079701435.

The spelling of 21696155 in words is "twenty-one million, six hundred ninety-six thousand, one hundred fifty-five".