725199421 has 2 divisors, whose sum is σ = 725199422. Its totient is φ = 725199420.

The previous prime is 725199401. The next prime is 725199427. The reversal of 725199421 is 124991527.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 695376900 + 29822521 = 26370^2 + 5461^2 .

It is an emirp because it is prime and its reverse (124991527) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 725199421 - 2¹⁷ = 725068349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (725199427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 362599710 + 362599711.

It is an arithmetic number, because the mean of its divisors is an integer number (362599711).

Almost surely, 2^725199421 is an apocalyptic number.

It is an amenable number.

725199421 is a deficient number, since it is larger than the sum of its proper divisors (1).

725199421 is an equidigital number, since it uses as much as digits as its factorization.

725199421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 40.

The square root of 725199421 is about 26929.5269360604. The cubic root of 725199421 is about 898.4332498517.

The spelling of 725199421 in words is "seven hundred twenty-five million, one hundred ninety-nine thousand, four hundred twenty-one".