21199772 has 12 divisors (see below), whose sum is σ = 40472376. Its totient is φ = 9636240.

The previous prime is 21199751. The next prime is 21199781. The reversal of 21199772 is 27799112.

It is a congruent 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, 240863 + ... + 240950.

It is an arithmetic number, because the mean of its divisors is an integer number (3372698).

Almost surely, 2^21199772 is an apocalyptic number.

21199772 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21199772 is a deficient number, since it is larger than the sum of its proper divisors (19272604).

21199772 is a wasteful number, since it uses less digits than its factorization.

21199772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481828 (or 481826 counting only the distinct ones).

The product of its digits is 15876, while the sum is 38.

The square root of 21199772 is about 4604.3210140041. The cubic root of 21199772 is about 276.7645085471.

The spelling of 21199772 in words is "twenty-one million, one hundred ninety-nine thousand, seven hundred seventy-two".