21869642 has 8 divisors (see below), whose sum is σ = 34230816. Its totient is φ = 10459372.

The previous prime is 21869641. The next prime is 21869669. The reversal of 21869642 is 24696812.

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 = 21869596 and 21869605.

It is not an unprimeable number, because it can be changed into a prime (21869641) 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, 237668 + ... + 237759.

It is an arithmetic number, because the mean of its divisors is an integer number (4278852).

Almost surely, 2^21869642 is an apocalyptic number.

21869642 is a deficient number, since it is larger than the sum of its proper divisors (12361174).

21869642 is a wasteful number, since it uses less digits than its factorization.

21869642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475452.

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

The square root of 21869642 is about 4676.4989040948. The cubic root of 21869642 is about 279.6493996164.

The spelling of 21869642 in words is "twenty-one million, eight hundred sixty-nine thousand, six hundred forty-two".