21323142 has 32 divisors (see below), whose sum is σ = 47554560. Its totient is φ = 7082280.

The previous prime is 21323129. The next prime is 21323153. The reversal of 21323142 is 24132312.

It is a super-3 number, since 3×21323142³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20167 + ... + 21197.

It is an arithmetic number, because the mean of its divisors is an integer number (1486080).

Almost surely, 2^21323142 is an apocalyptic number.

21323142 is an abundant number, since it is smaller than the sum of its proper divisors (26231418).

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

21323142 is a wasteful number, since it uses less digits than its factorization.

21323142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1425 (or 1419 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 21323142 is about 4617.6987775298. The cubic root of 21323142 is about 277.3003384815.

Adding to 21323142 its reverse (24132312), we get a palindrome (45455454).

The spelling of 21323142 in words is "twenty-one million, three hundred twenty-three thousand, one hundred forty-two".