19900378506 has 16 divisors (see below), whose sum is σ = 39901015584. Its totient is φ = 6616749744.

The previous prime is 19900378499. The next prime is 19900378507. The reversal of 19900378506 is 60587300991.

It is not an unprimeable number, because it can be changed into a prime (19900378507) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4174860 + ... + 4179623.

It is an arithmetic number, because the mean of its divisors is an integer number (2493813474).

Almost surely, 2^19900378506 is an apocalyptic number.

19900378506 is an abundant number, since it is smaller than the sum of its proper divisors (20000637078).

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

19900378506 is a wasteful number, since it uses less digits than its factorization.

19900378506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8354885.

The product of its (nonzero) digits is 408240, while the sum is 48.

The spelling of 19900378506 in words is "nineteen billion, nine hundred million, three hundred seventy-eight thousand, five hundred six".