19140311521 has 4 divisors (see below), whose sum is σ = 19156092052. Its totient is φ = 19124530992.

The previous prime is 19140311507. The next prime is 19140311551. The reversal of 19140311521 is 12511304191.

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 5965863121 + 13174448400 = 77239^2 + 114780^2 .

It is a cyclic number.

It is not a de Polignac number, because 19140311521 - 2¹⁵ = 19140278753 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19140311521.

It is not an unprimeable number, because it can be changed into a prime (19140311551) 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, 7888446 + ... + 7890871.

It is an arithmetic number, because the mean of its divisors is an integer number (4789023013).

Almost surely, 2^19140311521 is an apocalyptic number.

It is an amenable number.

19140311521 is a deficient number, since it is larger than the sum of its proper divisors (15780531).

19140311521 is a wasteful number, since it uses less digits than its factorization.

19140311521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15780530.

The product of its (nonzero) digits is 1080, while the sum is 28.

The spelling of 19140311521 in words is "nineteen billion, one hundred forty million, three hundred eleven thousand, five hundred twenty-one".