19451893943 has 4 divisors (see below), whose sum is σ = 19467878640. Its totient is φ = 19435909248.

The previous prime is 19451893939. The next prime is 19451893963. The reversal of 19451893943 is 34939815491.

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

It is a cyclic number.

It is not a de Polignac number, because 19451893943 - 2² = 19451893939 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19451893963) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7990523 + ... + 7992956.

It is an arithmetic number, because the mean of its divisors is an integer number (4866969660).

Almost surely, 2^19451893943 is an apocalyptic number.

19451893943 is a deficient number, since it is larger than the sum of its proper divisors (15984697).

19451893943 is a wasteful number, since it uses less digits than its factorization.

19451893943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15984696.

The product of its digits is 4199040, while the sum is 56.

The spelling of 19451893943 in words is "nineteen billion, four hundred fifty-one million, eight hundred ninety-three thousand, nine hundred forty-three".