865135280 has 40 divisors (see below), whose sum is σ = 2012777424. Its totient is φ = 345824000.

The previous prime is 865135277. The next prime is 865135309. The reversal of 865135280 is 82531568.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 168755 + ... + 173805.

Almost surely, 2^865135280 is an apocalyptic number.

865135280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

865135280 is an abundant number, since it is smaller than the sum of its proper divisors (1147642144).

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

865135280 is a wasteful number, since it uses less digits than its factorization.

865135280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7205 (or 7199 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 38.

The square root of 865135280 is about 29413.1820787891. The cubic root of 865135280 is about 952.8576117165.

The spelling of 865135280 in words is "eight hundred sixty-five million, one hundred thirty-five thousand, two hundred eighty".