1581404240 has 160 divisors (see below), whose sum is σ = 4125069312. Its totient is φ = 559872000.

The previous prime is 1581404239. The next prime is 1581404273. The reversal of 1581404240 is 424041851.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5835305 + ... + 5835575.

Almost surely, 2^1581404240 is an apocalyptic number.

1581404240 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 1581404240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2062534656).

1581404240 is an abundant number, since it is smaller than the sum of its proper divisors (2543665072).

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

1581404240 is a wasteful number, since it uses less digits than its factorization.

1581404240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509 (or 503 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 29.

The square root of 1581404240 is about 39766.8736513194. The cubic root of 1581404240 is about 1165.0582323364.

The spelling of 1581404240 in words is "one billion, five hundred eighty-one million, four hundred four thousand, two hundred forty".