19711940400 has 90 divisors (see below), whose sum is σ = 68405921220. Its totient is φ = 5256516480.

The previous prime is 19711940387. The next prime is 19711940429. The reversal of 19711940400 is 404911791.

It is a tau number, because it is divible by the number of its divisors (90).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2734170 + ... + 2741369.

Almost surely, 2^19711940400 is an apocalyptic number.

19711940400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19711940400 is an abundant number, since it is smaller than the sum of its proper divisors (48693980820).

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

19711940400 is a wasteful number, since it uses less digits than its factorization.

19711940400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5475563 (or 5475549 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The spelling of 19711940400 in words is "nineteen billion, seven hundred eleven million, nine hundred forty thousand, four hundred".