249918421 has 2 divisors, whose sum is σ = 249918422. Its totient is φ = 249918420.

The previous prime is 249918413. The next prime is 249918443. The reversal of 249918421 is 124819942.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 226502500 + 23415921 = 15050^2 + 4839^2 .

It is a cyclic number.

It is not a de Polignac number, because 249918421 - 2³ = 249918413 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (249918401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124959210 + 124959211.

It is an arithmetic number, because the mean of its divisors is an integer number (124959211).

Almost surely, 2^249918421 is an apocalyptic number.

It is an amenable number.

249918421 is a deficient number, since it is larger than the sum of its proper divisors (1).

249918421 is an equidigital number, since it uses as much as digits as its factorization.

249918421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41472, while the sum is 40.

The square root of 249918421 is about 15808.8083358614. The cubic root of 249918421 is about 629.8919954266.

The spelling of 249918421 in words is "two hundred forty-nine million, nine hundred eighteen thousand, four hundred twenty-one".