19781865607 has 48 divisors (see below), whose sum is σ = 24475336704. Its totient is φ = 15915312000.

The previous prime is 19781865581. The next prime is 19781865611. The reversal of 19781865607 is 70656818791.

It is not a de Polignac number, because 19781865607 - 2⁷ = 19781865479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19781865647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11894458 + ... + 11896120.

It is an arithmetic number, because the mean of its divisors is an integer number (509902848).

Almost surely, 2^19781865607 is an apocalyptic number.

19781865607 is a deficient number, since it is larger than the sum of its proper divisors (4693471097).

19781865607 is a wasteful number, since it uses less digits than its factorization.

19781865607 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1940 (or 1933 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 58.

The spelling of 19781865607 in words is "nineteen billion, seven hundred eighty-one million, eight hundred sixty-five thousand, six hundred seven".