1267431440 has 80 divisors (see below), whose sum is σ = 3241506816. Its totient is φ = 460845440.

The previous prime is 1267431421. The next prime is 1267431443. The reversal of 1267431440 is 441347621.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 1267431397 and 1267431406.

It is not an unprimeable number, because it can be changed into a prime (1267431443) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 100529 + ... + 112431.

Almost surely, 2^1267431440 is an apocalyptic number.

1267431440 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 1267431440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1620753408).

1267431440 is an abundant number, since it is smaller than the sum of its proper divisors (1974075376).

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

1267431440 is a wasteful number, since it uses less digits than its factorization.

1267431440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11949 (or 11921 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 1267431440 is about 35601.0033566471. The cubic root of 1267431440 is about 1082.2015676079.

The spelling of 1267431440 in words is "one billion, two hundred sixty-seven million, four hundred thirty-one thousand, four hundred forty".