21724463942 has 4 divisors (see below), whose sum is σ = 32586695916. Its totient is φ = 10862231970.

The previous prime is 21724463921. The next prime is 21724463951. The reversal of 21724463942 is 24936442712.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 21724463893 and 21724463902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5431115984 + ... + 5431115987.

It is an arithmetic number, because the mean of its divisors is an integer number (8146673979).

Almost surely, 2^21724463942 is an apocalyptic number.

21724463942 is a deficient number, since it is larger than the sum of its proper divisors (10862231974).

21724463942 is a wasteful number, since it uses less digits than its factorization.

21724463942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10862231973.

The product of its digits is 580608, while the sum is 44.

The spelling of 21724463942 in words is "twenty-one billion, seven hundred twenty-four million, four hundred sixty-three thousand, nine hundred forty-two".