1961009111 has 2 divisors, whose sum is σ = 1961009112. Its totient is φ = 1961009110.

The previous prime is 1961009107. The next prime is 1961009123. The reversal of 1961009111 is 1119001691.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1119001691) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 1116001961 and 1691006111.

It is a cyclic number.

It is not a de Polignac number, because 1961009111 - 2² = 1961009107 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1961009161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 980504555 + 980504556.

It is an arithmetic number, because the mean of its divisors is an integer number (980504556).

Almost surely, 2^1961009111 is an apocalyptic number.

1961009111 is a deficient number, since it is larger than the sum of its proper divisors (1).

1961009111 is an equidigital number, since it uses as much as digits as its factorization.

1961009111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 486, while the sum is 29.

The square root of 1961009111 is about 44283.2825228663. The cubic root of 1961009111 is about 1251.6796855941.

The spelling of 1961009111 in words is "one billion, nine hundred sixty-one million, nine thousand, one hundred eleven".