21728379674 has 8 divisors (see below), whose sum is σ = 32636437920. Its totient is φ = 10849567036.

The previous prime is 21728379649. The next prime is 21728379713. The reversal of 21728379674 is 47697382712.

It is a happy number.

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

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, 7309544 + ... + 7312515.

It is an arithmetic number, because the mean of its divisors is an integer number (4079554740).

Almost surely, 2^21728379674 is an apocalyptic number.

21728379674 is a deficient number, since it is larger than the sum of its proper divisors (10908058246).

21728379674 is a wasteful number, since it uses less digits than its factorization.

21728379674 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14622804.

The product of its digits is 7112448, while the sum is 56.

The spelling of 21728379674 in words is "twenty-one billion, seven hundred twenty-eight million, three hundred seventy-nine thousand, six hundred seventy-four".