745621 has 2 divisors, whose sum is σ = 745622. Its totient is φ = 745620.

The previous prime is 745609. The next prime is 745631. The reversal of 745621 is 126547.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 505521 + 240100 = 711^2 + 490^2 .

It is an emirp because it is prime and its reverse (126547) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 745621 - 2¹¹ = 743573 is a prime.

745621 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (745601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 372810 + 372811.

It is an arithmetic number, because the mean of its divisors is an integer number (372811).

2⁷⁴⁵⁶²¹ is an apocalyptic number.

It is an amenable number.

745621 is a deficient number, since it is larger than the sum of its proper divisors (1).

745621 is an equidigital number, since it uses as much as digits as its factorization.

745621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1680, while the sum is 25.

The square root of 745621 is about 863.4934857890. The cubic root of 745621 is about 90.6788583543.

The spelling of 745621 in words is "seven hundred forty-five thousand, six hundred twenty-one".