1904681 has 2 divisors, whose sum is σ = 1904682. Its totient is φ = 1904680.

The previous prime is 1904647. The next prime is 1904687. The reversal of 1904681 is 1864091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1525225 + 379456 = 1235^2 + 616^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1904681 is a prime.

It is a super-2 number, since 2×1904681² = 7255619423522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1904687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 952340 + 952341.

It is an arithmetic number, because the mean of its divisors is an integer number (952341).

2^1904681 is an apocalyptic number.

It is an amenable number.

1904681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1904681 is an equidigital number, since it uses as much as digits as its factorization.

1904681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 1904681 is about 1380.1018078388. The cubic root of 1904681 is about 123.9578637618.

The spelling of 1904681 in words is "one million, nine hundred four thousand, six hundred eighty-one".