19451297880 has 320 divisors, whose sum is σ = 78651936000. Its totient is φ = 4211917056.

The previous prime is 19451297863. The next prime is 19451297903. The reversal of 19451297880 is 8879215491.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 408351 + ... + 453489.

It is an arithmetic number, because the mean of its divisors is an integer number (245787300).

Almost surely, 2^19451297880 is an apocalyptic number.

19451297880 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 19451297880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39325968000).

19451297880 is an abundant number, since it is smaller than the sum of its proper divisors (59200638120).

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

19451297880 is a wasteful number, since it uses less digits than its factorization.

19451297880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45188 (or 45175 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 54.

The spelling of 19451297880 in words is "nineteen billion, four hundred fifty-one million, two hundred ninety-seven thousand, eight hundred eighty".