1279432320 has 128 divisors (see below), whose sum is σ = 4173301440. Its totient is φ = 333225984.

The previous prime is 1279432313. The next prime is 1279432321. The reversal of 1279432320 is 232349721.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×1279432320² = 3273894122921164800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1279432321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74812 + ... + 90308.

Almost surely, 2^1279432320 is an apocalyptic number.

1279432320 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 1279432320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2086650720).

1279432320 is an abundant number, since it is smaller than the sum of its proper divisors (2893869120).

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

1279432320 is a wasteful number, since it uses less digits than its factorization.

1279432320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15562 (or 15550 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 33.

The square root of 1279432320 is about 35769.1531909829. The cubic root of 1279432320 is about 1085.6065103413.

The spelling of 1279432320 in words is "one billion, two hundred seventy-nine million, four hundred thirty-two thousand, three hundred twenty".