1721452591 has 2 divisors, whose sum is σ = 1721452592. Its totient is φ = 1721452590.

The previous prime is 1721452559. The next prime is 1721452633. The reversal of 1721452591 is 1952541271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1721452591 - 2⁵ = 1721452559 is a prime.

It is a super-2 number, since 2×1721452591² = 5926798046121226562, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1721452591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1721452531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860726295 + 860726296.

It is an arithmetic number, because the mean of its divisors is an integer number (860726296).

Almost surely, 2^1721452591 is an apocalyptic number.

1721452591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1721452591 is an equidigital number, since it uses as much as digits as its factorization.

1721452591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25200, while the sum is 37.

The square root of 1721452591 is about 41490.3915503337. The cubic root of 1721452591 is about 1198.4824778124.

The spelling of 1721452591 in words is "one billion, seven hundred twenty-one million, four hundred fifty-two thousand, five hundred ninety-one".