249425821 has 2 divisors, whose sum is σ = 249425822. Its totient is φ = 249425820.

The previous prime is 249425807. The next prime is 249425833. The reversal of 249425821 is 128524942.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 180768025 + 68657796 = 13445^2 + 8286^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-249425821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (249425321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124712910 + 124712911.

It is an arithmetic number, because the mean of its divisors is an integer number (124712911).

Almost surely, 2^249425821 is an apocalyptic number.

It is an amenable number.

249425821 is a deficient number, since it is larger than the sum of its proper divisors (1).

249425821 is an equidigital number, since it uses as much as digits as its factorization.

249425821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46080, while the sum is 37.

The square root of 249425821 is about 15793.2207291610. The cubic root of 249425821 is about 629.4778751164.

The spelling of 249425821 in words is "two hundred forty-nine million, four hundred twenty-five thousand, eight hundred twenty-one".