1987261 has 2 divisors, whose sum is σ = 1987262. Its totient is φ = 1987260.

The previous prime is 1987247. The next prime is 1987277. The reversal of 1987261 is 1627891.

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., 1232100 + 755161 = 1110^2 + 869^2 .

It is a cyclic number.

It is not a de Polignac number, because 1987261 - 2⁹ = 1986749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1987201) 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 as a sum of consecutive naturals, namely, 993630 + 993631.

It is an arithmetic number, because the mean of its divisors is an integer number (993631).

2^1987261 is an apocalyptic number.

It is an amenable number.

1987261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1987261 is an equidigital number, since it uses as much as digits as its factorization.

1987261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 34.

The square root of 1987261 is about 1409.7024508739. The cubic root of 1987261 is about 125.7240327817.

The spelling of 1987261 in words is "one million, nine hundred eighty-seven thousand, two hundred sixty-one".