18951956647 has 8 divisors (see below), whose sum is σ = 20420687840. Its totient is φ = 17484780960.

The previous prime is 18951956633. The next prime is 18951956651. The reversal of 18951956647 is 74665915981.

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 18951956647 - 2⁷ = 18951956519 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 (18951951647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 363504 + ... + 412357.

It is an arithmetic number, because the mean of its divisors is an integer number (2552585980).

Almost surely, 2^18951956647 is an apocalyptic number.

18951956647 is a deficient number, since it is larger than the sum of its proper divisors (1468731193).

18951956647 is a wasteful number, since it uses less digits than its factorization.

18951956647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 777753.

The product of its digits is 16329600, while the sum is 61.

The spelling of 18951956647 in words is "eighteen billion, nine hundred fifty-one million, nine hundred fifty-six thousand, six hundred forty-seven".