1945723691664 has 75 divisors (see below), whose sum is σ = 5631634207507. Its totient is φ = 648557825184.

The previous prime is 1945723691633. The next prime is 1945723691677. The reversal of 1945723691664 is 4661963275491.

It is a happy number.

The square root of 1945723691664 is 1394892.

It is a perfect power (a square), and thus also a powerful number.

1945723691664 is a `hidden beast` number, since 1 + 9 + 45 + 72 + 369 + 166 + 4 = 666.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 50196739 + ... + 50235485.

Almost surely, 2^{1945723691664} is an apocalyptic number.

1945723691664 is the 1394892-nd square number.

It is an amenable number.

1945723691664 is an abundant number, since it is smaller than the sum of its proper divisors (3685910515843).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1945723691664 is an frugal number, since it uses more digits than its factorization.

1945723691664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77514 (or 38752 counting only the distinct ones).

The product of its digits is 58786560, while the sum is 63.

The spelling of 1945723691664 in words is "one trillion, nine hundred forty-five billion, seven hundred twenty-three million, six hundred ninety-one thousand, six hundred sixty-four".