21024722 has 8 divisors (see below), whose sum is σ = 31654272. Its totient is φ = 10473300.

The previous prime is 21024643. The next prime is 21024743. The reversal of 21024722 is 22742012.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 21024694 and 21024703.

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, 18854 + ... + 19937.

It is an arithmetic number, because the mean of its divisors is an integer number (3956784).

Almost surely, 2^21024722 is an apocalyptic number.

21024722 is a deficient number, since it is larger than the sum of its proper divisors (10629550).

21024722 is a wasteful number, since it uses less digits than its factorization.

21024722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39064.

The product of its (nonzero) digits is 448, while the sum is 20.

The square root of 21024722 is about 4585.2722928960. The cubic root of 21024722 is about 276.0006388699. Note that the first 3 decimals are identical.

Adding to 21024722 its reverse (22742012), we get a palindrome (43766734).

The spelling of 21024722 in words is "twenty-one million, twenty-four thousand, seven hundred twenty-two".