21251454142 has 8 divisors (see below), whose sum is σ = 32417472600. Its totient is φ = 10445629944.

The previous prime is 21251454089. The next prime is 21251454181. The reversal of 21251454142 is 24145415212.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90048417 + ... + 90048652.

It is an arithmetic number, because the mean of its divisors is an integer number (4052184075).

Almost surely, 2^21251454142 is an apocalyptic number.

21251454142 is a deficient number, since it is larger than the sum of its proper divisors (11166018458).

21251454142 is a wasteful number, since it uses less digits than its factorization.

21251454142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180097130.

The product of its digits is 12800, while the sum is 31.

Adding to 21251454142 its reverse (24145415212), we get a palindrome (45396869354).

The spelling of 21251454142 in words is "twenty-one billion, two hundred fifty-one million, four hundred fifty-four thousand, one hundred forty-two".