21178437142 has 8 divisors (see below), whose sum is σ = 32506438536. Its totient is φ = 10342957632.

The previous prime is 21178437139. The next prime is 21178437169. The reversal of 21178437142 is 24173487112.

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

It is a junction number, because it is equal to n+sod(n) for n = 21178437095 and 21178437104.

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, 123130363 + ... + 123130534.

It is an arithmetic number, because the mean of its divisors is an integer number (4063304817).

Almost surely, 2^21178437142 is an apocalyptic number.

21178437142 is a deficient number, since it is larger than the sum of its proper divisors (11328001394).

21178437142 is a wasteful number, since it uses less digits than its factorization.

21178437142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246260942.

The product of its digits is 75264, while the sum is 40.

The spelling of 21178437142 in words is "twenty-one billion, one hundred seventy-eight million, four hundred thirty-seven thousand, one hundred forty-two".