21159642 has 32 divisors (see below), whose sum is σ = 49190400. Its totient is φ = 5942448.

The previous prime is 21159641. The next prime is 21159643. The reversal of 21159642 is 24695112.

It is an interprime number because it is at equal distance from previous prime (21159641) and next prime (21159643).

It is not an unprimeable number, because it can be changed into a prime (21159641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1792 + ... + 6747.

It is an arithmetic number, because the mean of its divisors is an integer number (1537200).

Almost surely, 2^21159642 is an apocalyptic number.

21159642 is an abundant number, since it is smaller than the sum of its proper divisors (28030758).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21159642 is a wasteful number, since it uses less digits than its factorization.

21159642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8610.

The product of its digits is 4320, while the sum is 30.

The square root of 21159642 is about 4599.9610867919. The cubic root of 21159642 is about 276.5897649203.

The spelling of 21159642 in words is "twenty-one million, one hundred fifty-nine thousand, six hundred forty-two".