21378747574 has 8 divisors (see below), whose sum is σ = 32084217720. Its totient is φ = 10684008336.

The previous prime is 21378747499. The next prime is 21378747581. The reversal of 21378747574 is 47574787312.

It is a happy number.

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 pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2677744 + ... + 2685715.

It is an arithmetic number, because the mean of its divisors is an integer number (4010527215).

Almost surely, 2^21378747574 is an apocalyptic number.

21378747574 is a deficient number, since it is larger than the sum of its proper divisors (10705470146).

21378747574 is a wasteful number, since it uses less digits than its factorization.

21378747574 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5365454.

The product of its digits is 9219840, while the sum is 55.

The spelling of 21378747574 in words is "twenty-one billion, three hundred seventy-eight million, seven hundred forty-seven thousand, five hundred seventy-four".