19642380749 has 4 divisors (see below), whose sum is σ = 19891018560. Its totient is φ = 19393742940.

The previous prime is 19642380739. The next prime is 19642380761. The reversal of 19642380749 is 94708324691.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19642380749 - 2²⁰ = 19641332173 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 19642380749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19642380739) 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, 124318787 + ... + 124318944.

It is an arithmetic number, because the mean of its divisors is an integer number (4972754640).

Almost surely, 2^19642380749 is an apocalyptic number.

It is an amenable number.

19642380749 is a deficient number, since it is larger than the sum of its proper divisors (248637811).

19642380749 is an equidigital number, since it uses as much as digits as its factorization.

19642380749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248637810.

The product of its (nonzero) digits is 2612736, while the sum is 53.

The spelling of 19642380749 in words is "nineteen billion, six hundred forty-two million, three hundred eighty thousand, seven hundred forty-nine".