21342442 has 8 divisors (see below), whose sum is σ = 34924032. Its totient is φ = 9701100.

The previous prime is 21342437. The next prime is 21342443. The reversal of 21342442 is 24424312.

It is a happy number.

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

It is a Harshad number since it is a multiple of its sum of digits (22), and also a Moran number because the ratio is a prime number: 970111 = 21342442 / (2 + 1 + 3 + 4 + 2 + 4 + 4 + 2).

It is not an unprimeable number, because it can be changed into a prime (21342443) 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, 485034 + ... + 485077.

It is an arithmetic number, because the mean of its divisors is an integer number (4365504).

Almost surely, 2^21342442 is an apocalyptic number.

21342442 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21342442 is a deficient number, since it is larger than the sum of its proper divisors (13581590).

21342442 is a wasteful number, since it uses less digits than its factorization.

21342442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 970124.

The product of its digits is 1536, while the sum is 22.

The square root of 21342442 is about 4619.7880903782. The cubic root of 21342442 is about 277.3839766033.

Adding to 21342442 its reverse (24424312), we get a palindrome (45766754).

The spelling of 21342442 in words is "twenty-one million, three hundred forty-two thousand, four hundred forty-two".