21857802 has 16 divisors (see below), whose sum is σ = 44036352. Its totient is φ = 7232480.

The previous prime is 21857779. The next prime is 21857807. The reversal of 21857802 is 20875812.

It is not an unprimeable number, because it can be changed into a prime (21857807) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12474 + ... + 14117.

It is an arithmetic number, because the mean of its divisors is an integer number (2752272).

Almost surely, 2^21857802 is an apocalyptic number.

21857802 is an abundant number, since it is smaller than the sum of its proper divisors (22178550).

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

21857802 is a wasteful number, since it uses less digits than its factorization.

21857802 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26733.

The product of its (nonzero) digits is 8960, while the sum is 33.

The square root of 21857802 is about 4675.2328284268. The cubic root of 21857802 is about 279.5989240668.

The spelling of 21857802 in words is "twenty-one million, eight hundred fifty-seven thousand, eight hundred two".