189811396440 has 256 divisors, whose sum is σ = 640684800000. Its totient is φ = 49980395520.

The previous prime is 189811396427. The next prime is 189811396451. The reversal of 189811396440 is 44693118981.

189811396440 is a `hidden beast` number, since 1 + 89 + 8 + 113 + 9 + 6 + 440 = 666.

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 polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 52273425 + ... + 52277055.

It is an arithmetic number, because the mean of its divisors is an integer number (2502675000).

Almost surely, 2^189811396440 is an apocalyptic number.

189811396440 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 189811396440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (320342400000).

189811396440 is an abundant number, since it is smaller than the sum of its proper divisors (450873403560).

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

189811396440 is a wasteful number, since it uses less digits than its factorization.

189811396440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4247 (or 4237 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 54.

The spelling of 189811396440 in words is "one hundred eighty-nine billion, eight hundred eleven million, three hundred ninety-six thousand, four hundred forty".