21065426 has 16 divisors (see below), whose sum is σ = 32840640. Its totient is φ = 10122000.

The previous prime is 21065423. The next prime is 21065437. The reversal of 21065426 is 62456012.

It is a super-2 number, since 2×21065426² = 887504345122952, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21065395 and 21065404.

It is not an unprimeable number, because it can be changed into a prime (21065423) 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, 13835 + ... + 15281.

It is an arithmetic number, because the mean of its divisors is an integer number (2052540).

Almost surely, 2^21065426 is an apocalyptic number.

21065426 is a deficient number, since it is larger than the sum of its proper divisors (11775214).

21065426 is a wasteful number, since it uses less digits than its factorization.

21065426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1729.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 21065426 is about 4589.7087053538. The cubic root of 21065426 is about 276.1786370678.

The spelling of 21065426 in words is "twenty-one million, sixty-five thousand, four hundred twenty-six".