1001555965 has 8 divisors (see below), whose sum is σ = 1202343480. Its totient is φ = 800927232.

The previous prime is 1001555959. The next prime is 1001556001. The reversal of 1001555965 is 5695551001.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 11383876 + 990172089 = 3374^2 + 31467^2 .

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 1001555965 - 2⁹ = 1001555453 is a prime.

It is a super-2 number, since 2×1001555965² = 2006228702054162450, which contains 22 as substring.

It is a congruent number.

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, 25344 + ... + 51433.

It is an arithmetic number, because the mean of its divisors is an integer number (150292935).

Almost surely, 2^1001555965 is an apocalyptic number.

It is an amenable number.

1001555965 is a deficient number, since it is larger than the sum of its proper divisors (200787515).

1001555965 is an equidigital number, since it uses as much as digits as its factorization.

1001555965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79391.

The product of its (nonzero) digits is 33750, while the sum is 37.

The square root of 1001555965 is about 31647.3690059695. The cubic root of 1001555965 is about 1000.5183862293.

The spelling of 1001555965 in words is "one billion, one million, five hundred fifty-five thousand, nine hundred sixty-five".