1961481787 has 4 divisors (see below), whose sum is σ = 2029119120. Its totient is φ = 1893844456.

The previous prime is 1961481763. The next prime is 1961481793. The reversal of 1961481787 is 7871841691.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1961481787 - 2¹⁹ = 1960957499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1961481737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33818623 + ... + 33818680.

It is an arithmetic number, because the mean of its divisors is an integer number (507279780).

Almost surely, 2^1961481787 is an apocalyptic number.

1961481787 is a deficient number, since it is larger than the sum of its proper divisors (67637333).

1961481787 is an equidigital number, since it uses as much as digits as its factorization.

1961481787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67637332.

The product of its digits is 677376, while the sum is 52.

The square root of 1961481787 is about 44288.6191588765. The cubic root of 1961481787 is about 1251.7802446063.

The spelling of 1961481787 in words is "one billion, nine hundred sixty-one million, four hundred eighty-one thousand, seven hundred eighty-seven".