21423342 has 16 divisors (see below), whose sum is σ = 43655760. Its totient is φ = 7006272.

The previous prime is 21423319. The next prime is 21423343. The reversal of 21423342 is 24332412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21423343) 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, 33367 + ... + 34002.

It is an arithmetic number, because the mean of its divisors is an integer number (2728485).

Almost surely, 2^21423342 is an apocalyptic number.

21423342 is an abundant number, since it is smaller than the sum of its proper divisors (22232418).

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

21423342 is a wasteful number, since it uses less digits than its factorization.

21423342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67427.

The product of its digits is 1152, while the sum is 21.

The square root of 21423342 is about 4628.5356215546. The cubic root of 21423342 is about 277.7340157311.

Adding to 21423342 its reverse (24332412), we get a palindrome (45755754).

The spelling of 21423342 in words is "twenty-one million, four hundred twenty-three thousand, three hundred forty-two".