21140142 has 8 divisors (see below), whose sum is σ = 42280296. Its totient is φ = 7046712.

The previous prime is 21140123. The next prime is 21140149. The reversal of 21140142 is 24104112.

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

21140142 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21140149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1761673 + ... + 1761684.

It is an arithmetic number, because the mean of its divisors is an integer number (5285037).

Almost surely, 2^21140142 is an apocalyptic number.

21140142 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21140142 is a wasteful number, since it uses less digits than its factorization.

21140142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3523362.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 21140142 is about 4597.8410150852. The cubic root of 21140142 is about 276.5047735944.

Adding to 21140142 its reverse (24104112), we get a palindrome (45244254).

The spelling of 21140142 in words is "twenty-one million, one hundred forty thousand, one hundred forty-two".