1219861 has 2 divisors, whose sum is σ = 1219862. Its totient is φ = 1219860.

The previous prime is 1219859. The next prime is 1219871. The reversal of 1219861 is 1689121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 938961 + 280900 = 969^2 + 530^2 .

It is a cyclic number.

It is not a de Polignac number, because 1219861 - 2¹ = 1219859 is a prime.

Together with 1219859, it forms a pair of twin primes.

1219861 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1219811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609930 + 609931.

It is an arithmetic number, because the mean of its divisors is an integer number (609931).

2^1219861 is an apocalyptic number.

It is an amenable number.

1219861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1219861 is an equidigital number, since it uses as much as digits as its factorization.

1219861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 28.

The square root of 1219861 is about 1104.4731775829. The cubic root of 1219861 is about 106.8489147834.

It can be divided in two parts, 1219 and 861, that added together give a triangular number (2080 = T₆₄).

The spelling of 1219861 in words is "one million, two hundred nineteen thousand, eight hundred sixty-one".