181115420640 has 768 divisors, whose sum is σ = 751887360000. Its totient is φ = 35503349760.

The previous prime is 181115420617. The next prime is 181115420663. The reversal of 181115420640 is 46024511181.

It is an interprime number because it is at equal distance from previous prime (181115420617) and next prime (181115420663).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 245081391 + ... + 245082129.

It is an arithmetic number, because the mean of its divisors is an integer number (979020000).

Almost surely, 2^181115420640 is an apocalyptic number.

181115420640 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 181115420640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (375943680000).

181115420640 is an abundant number, since it is smaller than the sum of its proper divisors (570771939360).

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

181115420640 is a wasteful number, since it uses less digits than its factorization.

181115420640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1143 (or 1135 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 33.

It can be divided in two parts, 1811 and 15420640, that added together give a palindrome (15422451).

The spelling of 181115420640 in words is "one hundred eighty-one billion, one hundred fifteen million, four hundred twenty thousand, six hundred forty".