19661957814 has 32 divisors (see below), whose sum is σ = 39826805760. Its totient is φ = 6470286752.

The previous prime is 19661957807. The next prime is 19661957837. The reversal of 19661957814 is 41875916691.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 702904 + ... + 730340.

It is an arithmetic number, because the mean of its divisors is an integer number (1244587680).

Almost surely, 2^19661957814 is an apocalyptic number.

19661957814 is an abundant number, since it is smaller than the sum of its proper divisors (20164847946).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19661957814 is a wasteful number, since it uses less digits than its factorization.

19661957814 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28964.

The product of its digits is 3265920, while the sum is 57.

The spelling of 19661957814 in words is "nineteen billion, six hundred sixty-one million, nine hundred fifty-seven thousand, eight hundred fourteen".