21533154 has 8 divisors (see below), whose sum is σ = 43066320. Its totient is φ = 7177716.

The previous prime is 21533143. The next prime is 21533177. The reversal of 21533154 is 45133512.

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

21533154 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1794424 + ... + 1794435.

It is an arithmetic number, because the mean of its divisors is an integer number (5383290).

Almost surely, 2^21533154 is an apocalyptic number.

21533154 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21533154 is a wasteful number, since it uses less digits than its factorization.

21533154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3588864.

The product of its digits is 1800, while the sum is 24.

The square root of 21533154 is about 4640.3829583344. The cubic root of 21533154 is about 278.2077445846.

Adding to 21533154 its reverse (45133512), we get a palindrome (66666666).

The spelling of 21533154 in words is "twenty-one million, five hundred thirty-three thousand, one hundred fifty-four".