21147722 has 8 divisors (see below), whose sum is σ = 33391200. Its totient is φ = 10017324.

The previous prime is 21147713. The next prime is 21147727. The reversal of 21147722 is 22774112.

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

It is a super-2 number, since 2×21147722² = 894452291578568, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21147691 and 21147700.

It is not an unprimeable number, because it can be changed into a prime (21147727) 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, 278222 + ... + 278297.

It is an arithmetic number, because the mean of its divisors is an integer number (4173900).

Almost surely, 2^21147722 is an apocalyptic number.

21147722 is a deficient number, since it is larger than the sum of its proper divisors (12243478).

21147722 is a wasteful number, since it uses less digits than its factorization.

21147722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556540.

The product of its digits is 1568, while the sum is 26.

The square root of 21147722 is about 4598.6652411325. The cubic root of 21147722 is about 276.5378174552.

The spelling of 21147722 in words is "twenty-one million, one hundred forty-seven thousand, seven hundred twenty-two".