1961981336 has 32 divisors (see below), whose sum is σ = 4205671680. Its totient is φ = 840564000.

The previous prime is 1961981321. The next prime is 1961981347. The reversal of 1961981336 is 6331891691.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 300911 + ... + 307361.

It is an arithmetic number, because the mean of its divisors is an integer number (131427240).

Almost surely, 2^1961981336 is an apocalyptic number.

It is an amenable number.

1961981336 is an abundant number, since it is smaller than the sum of its proper divisors (2243690344).

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

1961981336 is a wasteful number, since it uses less digits than its factorization.

1961981336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11895 (or 11891 counting only the distinct ones).

The product of its digits is 209952, while the sum is 47.

The square root of 1961981336 is about 44294.2584992683. The cubic root of 1961981336 is about 1251.8865031325.

The spelling of 1961981336 in words is "one billion, nine hundred sixty-one million, nine hundred eighty-one thousand, three hundred thirty-six".