1961934987 has 18 divisors (see below), whose sum is σ = 2651684308. Its totient is φ = 1290311288.

The previous prime is 1961934971. The next prime is 1961935033. The reversal of 1961934987 is 7894391691.

It is not a de Polignac number, because 1961934987 - 2⁴ = 1961934971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1961934907) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 8208814 + ... + 8209052.

Almost surely, 2^1961934987 is an apocalyptic number.

1961934987 is a deficient number, since it is larger than the sum of its proper divisors (689749321).

1961934987 is an frugal number, since it uses more digits than its factorization.

1961934987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 695 (or 349 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 57.

The square root of 1961934987 is about 44293.7353019589. The cubic root of 1961934987 is about 1251.8766450461.

The spelling of 1961934987 in words is "one billion, nine hundred sixty-one million, nine hundred thirty-four thousand, nine hundred eighty-seven".