981956309 has 4 divisors (see below), whose sum is σ = 1033638240. Its totient is φ = 930274380.

The previous prime is 981956263. The next prime is 981956359. The reversal of 981956309 is 903659189.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-981956309 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981956359) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25840937 + ... + 25840974.

It is an arithmetic number, because the mean of its divisors is an integer number (258409560).

Almost surely, 2^981956309 is an apocalyptic number.

It is an amenable number.

981956309 is a deficient number, since it is larger than the sum of its proper divisors (51681931).

981956309 is a wasteful number, since it uses less digits than its factorization.

981956309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51681930.

The product of its (nonzero) digits is 524880, while the sum is 50.

The square root of 981956309 is about 31336.1821063128. The cubic root of 981956309 is about 993.9488943088.

The spelling of 981956309 in words is "nine hundred eighty-one million, nine hundred fifty-six thousand, three hundred nine".