1961542987 has 16 divisors (see below), whose sum is σ = 2011360032. Its totient is φ = 1912458240.

The previous prime is 1961542883. The next prime is 1961543029. The reversal of 1961542987 is 7892451691.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1961542987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1961542487) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 4659037 + ... + 4659457.

It is an arithmetic number, because the mean of its divisors is an integer number (125710002).

Almost surely, 2^1961542987 is an apocalyptic number.

1961542987 is a deficient number, since it is larger than the sum of its proper divisors (49817045).

1961542987 is a wasteful number, since it uses less digits than its factorization.

1961542987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1038.

The product of its digits is 1088640, while the sum is 52.

The square root of 1961542987 is about 44289.3100759088. The cubic root of 1961542987 is about 1251.7932633616.

The spelling of 1961542987 in words is "one billion, nine hundred sixty-one million, five hundred forty-two thousand, nine hundred eighty-seven".