1939661 has 4 divisors (see below), whose sum is σ = 1946172. Its totient is φ = 1933152.

The previous prime is 1939657. The next prime is 1939673. The reversal of 1939661 is 1669391.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 265225 + 1674436 = 515^2 + 1294^2 .

It is a cyclic number.

It is not a de Polignac number, because 1939661 - 2² = 1939657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1939621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2786 + ... + 3411.

It is an arithmetic number, because the mean of its divisors is an integer number (486543).

2^1939661 is an apocalyptic number.

It is an amenable number.

1939661 is a deficient number, since it is larger than the sum of its proper divisors (6511).

1939661 is an equidigital number, since it uses as much as digits as its factorization.

1939661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6510.

The product of its digits is 8748, while the sum is 35.

The square root of 1939661 is about 1392.7171284938. The cubic root of 1939661 is about 124.7121054428.

The spelling of 1939661 in words is "one million, nine hundred thirty-nine thousand, six hundred sixty-one".