1965885381 has 24 divisors (see below), whose sum is σ = 2896148736. Its totient is φ = 1284547680.

The previous prime is 1965885377. The next prime is 1965885413. The reversal of 1965885381 is 1835885691.

1965885381 is a `hidden beast` number, since 1 + 9 + 6 + 588 + 53 + 8 + 1 = 666.

It is not a de Polignac number, because 1965885381 - 2² = 1965885377 is a prime.

It is a super-2 number, since 2×1965885381² = 7729410662459030322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1965885301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 734676 + ... + 737346.

It is an arithmetic number, because the mean of its divisors is an integer number (120672864).

Almost surely, 2^1965885381 is an apocalyptic number.

It is an amenable number.

1965885381 is a deficient number, since it is larger than the sum of its proper divisors (930263355).

1965885381 is a wasteful number, since it uses less digits than its factorization.

1965885381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4273 (or 4270 counting only the distinct ones).

The product of its digits is 2073600, while the sum is 54.

The square root of 1965885381 is about 44338.3060231218. The cubic root of 1965885381 is about 1252.7163076758.

The spelling of 1965885381 in words is "one billion, nine hundred sixty-five million, eight hundred eighty-five thousand, three hundred eighty-one".