1721684087 has 2 divisors, whose sum is σ = 1721684088. Its totient is φ = 1721684086.

The previous prime is 1721684071. The next prime is 1721684101. The reversal of 1721684087 is 7804861271.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1721684087 - 2⁴ = 1721684071 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1721684017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860842043 + 860842044.

It is an arithmetic number, because the mean of its divisors is an integer number (860842044).

Almost surely, 2^1721684087 is an apocalyptic number.

1721684087 is a deficient number, since it is larger than the sum of its proper divisors (1).

1721684087 is an equidigital number, since it uses as much as digits as its factorization.

1721684087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 150528, while the sum is 44.

The square root of 1721684087 is about 41493.1812108930. The cubic root of 1721684087 is about 1198.5361982315.

The spelling of 1721684087 in words is "one billion, seven hundred twenty-one million, six hundred eighty-four thousand, eighty-seven".