21120024142 has 24 divisors (see below), whose sum is σ = 38211623856. Its totient is φ = 8575045344.

The previous prime is 21120024139. The next prime is 21120024143. The reversal of 21120024142 is 24142002112.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120024143) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2084383 + ... + 2094490.

It is an arithmetic number, because the mean of its divisors is an integer number (1592150994).

Almost surely, 2^21120024142 is an apocalyptic number.

21120024142 is a deficient number, since it is larger than the sum of its proper divisors (17091599714).

21120024142 is a wasteful number, since it uses less digits than its factorization.

21120024142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4178920 (or 4178901 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21120024142 its reverse (24142002112), we get a palindrome (45262026254).

The spelling of 21120024142 in words is "twenty-one billion, one hundred twenty million, twenty-four thousand, one hundred forty-two".