21426869 has 8 divisors (see below), whose sum is σ = 22410432. Its totient is φ = 20447680.

The previous prime is 21426841. The next prime is 21426901. The reversal of 21426869 is 96862412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21426869 is a prime.

It is a super-2 number, since 2×21426869² = 918221430286322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21426809) 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, 12854 + ... + 14424.

It is an arithmetic number, because the mean of its divisors is an integer number (2801304).

Almost surely, 2^21426869 is an apocalyptic number.

It is an amenable number.

21426869 is a deficient number, since it is larger than the sum of its proper divisors (983563).

21426869 is a wasteful number, since it uses less digits than its factorization.

21426869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2187.

The product of its digits is 41472, while the sum is 38.

The square root of 21426869 is about 4628.9166119082. The cubic root of 21426869 is about 277.7492563368.

The spelling of 21426869 in words is "twenty-one million, four hundred twenty-six thousand, eight hundred sixty-nine".