1281623040 has 352 divisors, whose sum is σ = 4653404160. Its totient is φ = 334430208.

The previous prime is 1281623039. The next prime is 1281623069. The reversal of 1281623040 is 403261821.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 1281622995 and 1281623013.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10091457 + ... + 10091583.

Almost surely, 2^1281623040 is an apocalyptic number.

1281623040 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 1281623040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2326702080).

1281623040 is an abundant number, since it is smaller than the sum of its proper divisors (3371781120).

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

1281623040 is a wasteful number, since it uses less digits than its factorization.

1281623040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234 (or 210 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 1281623040 is about 35799.7631277080. The cubic root of 1281623040 is about 1086.2257703437.

Adding to 1281623040 its reverse (403261821), we get a palindrome (1684884861).

The spelling of 1281623040 in words is "one billion, two hundred eighty-one million, six hundred twenty-three thousand, forty".