581990640 has 360 divisors, whose sum is σ = 2312508240. Its totient is φ = 120637440.

The previous prime is 581990639. The next prime is 581990663. The reversal of 581990640 is 46099185.

581990640 = 116² + 117² + ... + 1204².

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 581990592 and 581990601.

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 71 ways as a sum of consecutive naturals, for example, 1422756 + ... + 1423164.

It is an arithmetic number, because the mean of its divisors is an integer number (6423634).

Almost surely, 2^581990640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 581990640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1156254120).

581990640 is an abundant number, since it is smaller than the sum of its proper divisors (1730517600).

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

581990640 is a wasteful number, since it uses less digits than its factorization.

581990640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461 (or 437 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 581990640 is about 24124.4821706083. The cubic root of 581990640 is about 834.9080850695.

The spelling of 581990640 in words is "five hundred eighty-one million, nine hundred ninety thousand, six hundred forty".