245507621 has 2 divisors, whose sum is σ = 245507622. Its totient is φ = 245507620.

The previous prime is 245507611. The next prime is 245507623. The reversal of 245507621 is 126705542.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 171976996 + 73530625 = 13114^2 + 8575^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245507621 is a prime.

Together with 245507623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (245507623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122753810 + 122753811.

It is an arithmetic number, because the mean of its divisors is an integer number (122753811).

Almost surely, 2^245507621 is an apocalyptic number.

It is an amenable number.

245507621 is a deficient number, since it is larger than the sum of its proper divisors (1).

245507621 is an equidigital number, since it uses as much as digits as its factorization.

245507621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 245507621 is about 15668.6828099876. The cubic root of 245507621 is about 626.1643328329.

The spelling of 245507621 in words is "two hundred forty-five million, five hundred seven thousand, six hundred twenty-one".