21982426 has 4 divisors (see below), whose sum is σ = 32973642. Its totient is φ = 10991212.

The previous prime is 21982423. The next prime is 21982427. The reversal of 21982426 is 62428912.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20295025 + 1687401 = 4505^2 + 1299^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21982391 and 21982400.

It is not an unprimeable number, because it can be changed into a prime (21982423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5495605 + ... + 5495608.

Almost surely, 2^21982426 is an apocalyptic number.

21982426 is a deficient number, since it is larger than the sum of its proper divisors (10991216).

21982426 is a wasteful number, since it uses less digits than its factorization.

21982426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10991215.

The product of its digits is 13824, while the sum is 34.

The square root of 21982426 is about 4688.5419908539. The cubic root of 21982426 is about 280.1293025245.

It can be divided in two parts, 2198 and 2426, that added together give a square (4624 = 68²).

The spelling of 21982426 in words is "twenty-one million, nine hundred eighty-two thousand, four hundred twenty-six".