21573802 has 8 divisors (see below), whose sum is σ = 32681412. Its totient is φ = 10680000.

The previous prime is 21573791. The next prime is 21573803. The reversal of 21573802 is 20837512.

It can be written as a sum of positive squares in 2 ways, for example, as 21261321 + 312481 = 4611^2 + 559^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21573803) 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, 53199 + ... + 53602.

Almost surely, 2^21573802 is an apocalyptic number.

21573802 is a deficient number, since it is larger than the sum of its proper divisors (11107610).

21573802 is a wasteful number, since it uses less digits than its factorization.

21573802 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106904.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 21573802 is about 4644.7607042775. The cubic root of 21573802 is about 278.3826915545.

The spelling of 21573802 in words is "twenty-one million, five hundred seventy-three thousand, eight hundred two".