1961899 has 2 divisors, whose sum is σ = 1961900. Its totient is φ = 1961898.

The previous prime is 1961893. The next prime is 1961903. The reversal of 1961899 is 9981691.

It is a strong prime.

It is an emirp because it is prime and its reverse (9981691) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1961899 is a prime.

It is not a weakly prime, because it can be changed into another prime (1961893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 980949 + 980950.

It is an arithmetic number, because the mean of its divisors is an integer number (980950).

2^1961899 is an apocalyptic number.

1961899 is a deficient number, since it is larger than the sum of its proper divisors (1).

1961899 is an equidigital number, since it uses as much as digits as its factorization.

1961899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34992, while the sum is 43.

The square root of 1961899 is about 1400.6780500886. The cubic root of 1961899 is about 125.1868990773.

The spelling of 1961899 in words is "one million, nine hundred sixty-one thousand, eight hundred ninety-nine".