21354155 has 8 divisors (see below), whose sum is σ = 25693200. Its totient is φ = 17037856.

The previous prime is 21354139. The next prime is 21354167. The reversal of 21354155 is 55145312.

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 21354155 - 2⁴ = 21354139 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, 3545 + ... + 7434.

It is an arithmetic number, because the mean of its divisors is an integer number (3211650).

Almost surely, 2^21354155 is an apocalyptic number.

21354155 is a deficient number, since it is larger than the sum of its proper divisors (4339045).

21354155 is a wasteful number, since it uses less digits than its factorization.

21354155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11373.

The product of its digits is 3000, while the sum is 26.

The square root of 21354155 is about 4621.0556153329. The cubic root of 21354155 is about 277.4347112589.

Adding to 21354155 its reverse (55145312), we get a palindrome (76499467).

The spelling of 21354155 in words is "twenty-one million, three hundred fifty-four thousand, one hundred fifty-five".