1903661 has 2 divisors, whose sum is σ = 1903662. Its totient is φ = 1903660.

The previous prime is 1903651. The next prime is 1903669. The reversal of 1903661 is 1663091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1705636 + 198025 = 1306^2 + 445^2 .

It is an emirp because it is prime and its reverse (1663091) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1903661 - 2⁶ = 1903597 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1903661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1903669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 951830 + 951831.

It is an arithmetic number, because the mean of its divisors is an integer number (951831).

2^1903661 is an apocalyptic number.

It is an amenable number.

1903661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1903661 is an equidigital number, since it uses as much as digits as its factorization.

1903661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 1903661 is about 1379.7322203964. The cubic root of 1903661 is about 123.9357323921.

The spelling of 1903661 in words is "one million, nine hundred three thousand, six hundred sixty-one".