1903681 has 4 divisors (see below), whose sum is σ = 2050132. Its totient is φ = 1757232.

The previous prime is 1903673. The next prime is 1903703. The reversal of 1903681 is 1863091.

It is a happy number.

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 921600 + 982081 = 960^2 + 991^2 .

It is a cyclic number.

It is not a de Polignac number, because 1903681 - 2³ = 1903673 is a prime.

It is a super-2 number, since 2×1903681² = 7248002699522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1903651) 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, 73206 + ... + 73231.

It is an arithmetic number, because the mean of its divisors is an integer number (512533).

2^1903681 is an apocalyptic number.

It is an amenable number.

1903681 is a deficient number, since it is larger than the sum of its proper divisors (146451).

1903681 is a wasteful number, since it uses less digits than its factorization.

1903681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146450.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1903681 is about 1379.7394681606. The cubic root of 1903681 is about 123.9361664165.

The spelling of 1903681 in words is "one million, nine hundred three thousand, six hundred eighty-one".