1721525661403 has 2 divisors, whose sum is σ = 1721525661404. Its totient is φ = 1721525661402.

The previous prime is 1721525661311. The next prime is 1721525661431. The reversal of 1721525661403 is 3041665251271.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1721525661403 - 2⁹ = 1721525660891 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1721525661403.

It is not a weakly prime, because it can be changed into another prime (1721525661433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860762830701 + 860762830702.

It is an arithmetic number, because the mean of its divisors is an integer number (860762830702).

Almost surely, 2^{1721525661403} is an apocalyptic number.

1721525661403 is a deficient number, since it is larger than the sum of its proper divisors (1).

1721525661403 is an equidigital number, since it uses as much as digits as its factorization.

1721525661403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 302400, while the sum is 43.

The spelling of 1721525661403 in words is "one trillion, seven hundred twenty-one billion, five hundred twenty-five million, six hundred sixty-one thousand, four hundred three".