19956371705 has 8 divisors (see below), whose sum is σ = 24988848192. Its totient is φ = 15270962608.

The previous prime is 19956371683. The next prime is 19956371749. The reversal of 19956371705 is 50717365991.

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

It is a de Polignac number, because none of the positive numbers 2^k-19956371705 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, 86766719 + ... + 86766948.

It is an arithmetic number, because the mean of its divisors is an integer number (3123606024).

Almost surely, 2^19956371705 is an apocalyptic number.

It is an amenable number.

19956371705 is a deficient number, since it is larger than the sum of its proper divisors (5032476487).

19956371705 is a wasteful number, since it uses less digits than its factorization.

19956371705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173533695.

The product of its (nonzero) digits is 1786050, while the sum is 53.

The spelling of 19956371705 in words is "nineteen billion, nine hundred fifty-six million, three hundred seventy-one thousand, seven hundred five".