19860961 has 4 divisors (see below), whose sum is σ = 19877572. Its totient is φ = 19844352.

The previous prime is 19860923. The next prime is 19860977. The reversal of 19860961 is 16906891.

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

It can be written as a sum of positive squares in 2 ways, for example, as 9492561 + 10368400 = 3081^2 + 3220^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19860961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19860991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6360 + ... + 8953.

It is an arithmetic number, because the mean of its divisors is an integer number (4969393).

Almost surely, 2^19860961 is an apocalyptic number.

It is an amenable number.

19860961 is a deficient number, since it is larger than the sum of its proper divisors (16611).

19860961 is a wasteful number, since it uses less digits than its factorization.

19860961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16610.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 19860961 is about 4456.5638108300. The cubic root of 19860961 is about 270.8112818548.

The spelling of 19860961 in words is "nineteen million, eight hundred sixty thousand, nine hundred sixty-one".