3619981 has 2 divisors, whose sum is σ = 3619982. Its totient is φ = 3619980.

The previous prime is 3619961. The next prime is 3619991. The reversal of 3619981 is 1899163.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3575881 + 44100 = 1891^2 + 210^2 .

It is a cyclic number.

It is not a de Polignac number, because 3619981 - 2¹³ = 3611789 is a prime.

It is a super-2 number, since 2×3619981² = 26208524880722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 3619981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3619921) 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, 1809990 + 1809991.

It is an arithmetic number, because the mean of its divisors is an integer number (1809991).

Almost surely, 2^3619981 is an apocalyptic number.

It is an amenable number.

3619981 is a deficient number, since it is larger than the sum of its proper divisors (1).

3619981 is an equidigital number, since it uses as much as digits as its factorization.

3619981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 37.

The square root of 3619981 is about 1902.6247659483. The cubic root of 3619981 is about 153.5449121799.

The spelling of 3619981 in words is "three million, six hundred nineteen thousand, nine hundred eighty-one".