1945397721619 has 8 divisors (see below), whose sum is σ = 2131131778560. Its totient is φ = 1761143617800.

The previous prime is 1945397721599. The next prime is 1945397721629. The reversal of 1945397721619 is 9161277935491.

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 1945397721619 - 2¹¹ = 1945397719571 is a prime.

It is a super-2 number, since 2×1945397721619² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1945397721629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 369985527 + ... + 369990784.

It is an arithmetic number, because the mean of its divisors is an integer number (266391472320).

Almost surely, 2^{1945397721619} is an apocalyptic number.

1945397721619 is a deficient number, since it is larger than the sum of its proper divisors (185734056941).

1945397721619 is a wasteful number, since it uses less digits than its factorization.

1945397721619 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739976561.

The product of its digits is 25719120, while the sum is 64.

The spelling of 1945397721619 in words is "one trillion, nine hundred forty-five billion, three hundred ninety-seven million, seven hundred twenty-one thousand, six hundred nineteen".