21634854 has 8 divisors (see below), whose sum is σ = 43269720. Its totient is φ = 7211616.

The previous prime is 21634853. The next prime is 21634871. The reversal of 21634854 is 45843612.

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

21634854 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21634853) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1802899 + ... + 1802910.

It is an arithmetic number, because the mean of its divisors is an integer number (5408715).

Almost surely, 2^21634854 is an apocalyptic number.

21634854 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.

21634854 is a wasteful number, since it uses less digits than its factorization.

21634854 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3605814.

The product of its digits is 23040, while the sum is 33.

The square root of 21634854 is about 4651.3281974077. The cubic root of 21634854 is about 278.6450439053.

The spelling of 21634854 in words is "twenty-one million, six hundred thirty-four thousand, eight hundred fifty-four".