21725386 has 16 divisors (see below), whose sum is σ = 34167744. Its totient is φ = 10340704.

The previous prime is 21725383. The next prime is 21725411. The reversal of 21725386 is 68352712.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21725383) 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, 9705 + ... + 11731.

It is an arithmetic number, because the mean of its divisors is an integer number (2135484).

Almost surely, 2^21725386 is an apocalyptic number.

21725386 is a deficient number, since it is larger than the sum of its proper divisors (12442358).

21725386 is a wasteful number, since it uses less digits than its factorization.

21725386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2285.

The product of its digits is 20160, while the sum is 34.

The square root of 21725386 is about 4661.0498817327. The cubic root of 21725386 is about 279.0331705186.

The spelling of 21725386 in words is "twenty-one million, seven hundred twenty-five thousand, three hundred eighty-six".