21375942745 has 8 divisors (see below), whose sum is σ = 26766398016. Its totient is φ = 16357243056.

The previous prime is 21375942733. The next prime is 21375942773. The reversal of 21375942745 is 54724957312.

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

It is a cyclic number.

It is not a de Polignac number, because 21375942745 - 2¹⁵ = 21375909977 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 92938767 + ... + 92938996.

It is an arithmetic number, because the mean of its divisors is an integer number (3345799752).

Almost surely, 2^21375942745 is an apocalyptic number.

It is an amenable number.

21375942745 is a deficient number, since it is larger than the sum of its proper divisors (5390455271).

21375942745 is a wasteful number, since it uses less digits than its factorization.

21375942745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185877791.

The product of its digits is 2116800, while the sum is 49.

The spelling of 21375942745 in words is "twenty-one billion, three hundred seventy-five million, nine hundred forty-two thousand, seven hundred forty-five".