19420957645 has 4 divisors (see below), whose sum is σ = 23305149180. Its totient is φ = 15536766112.

The previous prime is 19420957601. The next prime is 19420957651. The reversal of 19420957645 is 54675902491.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6587919556 + 12833038089 = 81166^2 + 113283^2 .

It is a cyclic number.

It is not a de Polignac number, because 19420957645 - 2¹⁵ = 19420924877 is a prime.

It is a super-3 number, since 3×19420957645³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19420957592 and 19420957601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1942095760 + ... + 1942095769.

It is an arithmetic number, because the mean of its divisors is an integer number (5826287295).

Almost surely, 2^19420957645 is an apocalyptic number.

It is an amenable number.

19420957645 is a deficient number, since it is larger than the sum of its proper divisors (3884191535).

19420957645 is an equidigital number, since it uses as much as digits as its factorization.

19420957645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3884191534.

The product of its (nonzero) digits is 2721600, while the sum is 52.

The spelling of 19420957645 in words is "nineteen billion, four hundred twenty million, nine hundred fifty-seven thousand, six hundred forty-five".