1861961 has 2 divisors, whose sum is σ = 1861962. Its totient is φ = 1861960.

The previous prime is 1861927. The next prime is 1861973. The reversal of 1861961 is 1691681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1336336 + 525625 = 1156^2 + 725^2 .

It is an emirp because it is prime and its reverse (1691681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1861961 - 2⁶ = 1861897 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1861921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 930980 + 930981.

It is an arithmetic number, because the mean of its divisors is an integer number (930981).

2^1861961 is an apocalyptic number.

It is an amenable number.

1861961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1861961 is an equidigital number, since it uses as much as digits as its factorization.

1861961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 32.

The square root of 1861961 is about 1364.5369177857. The cubic root of 1861961 is about 123.0240990963.

The spelling of 1861961 in words is "one million, eight hundred sixty-one thousand, nine hundred sixty-one".