19426508640 has 1152 divisors, whose sum is σ = 88197258240. Its totient is φ = 3997486080.

The previous prime is 19426508597. The next prime is 19426508641. The reversal of 19426508640 is 4680562491.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19426508641) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 188606829 + ... + 188606931.

It is an arithmetic number, because the mean of its divisors is an integer number (76560120).

Almost surely, 2^19426508640 is an apocalyptic number.

19426508640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19426508640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44098629120).

19426508640 is an abundant number, since it is smaller than the sum of its proper divisors (68770749600).

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

19426508640 is a wasteful number, since it uses less digits than its factorization.

19426508640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The spelling of 19426508640 in words is "nineteen billion, four hundred twenty-six million, five hundred eight thousand, six hundred forty".