1265783321 has 8 divisors (see below), whose sum is σ = 1390001088. Its totient is φ = 1143090000.

The previous prime is 1265783317. The next prime is 1265783371. The reversal of 1265783321 is 1233875621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1265783321 - 2² = 1265783317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265783371) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 379370 + ... + 382691.

It is an arithmetic number, because the mean of its divisors is an integer number (173750136).

Almost surely, 2^1265783321 is an apocalyptic number.

1265783321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1265783321 is a deficient number, since it is larger than the sum of its proper divisors (124217767).

1265783321 is a wasteful number, since it uses less digits than its factorization.

1265783321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 762223.

The product of its digits is 60480, while the sum is 38.

The square root of 1265783321 is about 35577.8487404733. The cubic root of 1265783321 is about 1081.7322797303.

The spelling of 1265783321 in words is "one billion, two hundred sixty-five million, seven hundred eighty-three thousand, three hundred twenty-one".