259640621 has 2 divisors, whose sum is σ = 259640622. Its totient is φ = 259640620.

The previous prime is 259640617. The next prime is 259640663. The reversal of 259640621 is 126046952.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 222904900 + 36735721 = 14930^2 + 6061^2 .

It is a cyclic number.

It is not a de Polignac number, because 259640621 - 2² = 259640617 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (259640671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 129820310 + 129820311.

It is an arithmetic number, because the mean of its divisors is an integer number (129820311).

Almost surely, 2^259640621 is an apocalyptic number.

It is an amenable number.

259640621 is a deficient number, since it is larger than the sum of its proper divisors (1).

259640621 is an equidigital number, since it uses as much as digits as its factorization.

259640621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 259640621 is about 16113.3677733738. The cubic root of 259640621 is about 637.9562253159.

The spelling of 259640621 in words is "two hundred fifty-nine million, six hundred forty thousand, six hundred twenty-one".