290320621 has 2 divisors, whose sum is σ = 290320622. Its totient is φ = 290320620.

The previous prime is 290320607. The next prime is 290320643. The reversal of 290320621 is 126023092.

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., 241460521 + 48860100 = 15539^2 + 6990^2 .

It is a cyclic number.

It is not a de Polignac number, because 290320621 - 2⁹ = 290320109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (290320661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145160310 + 145160311.

It is an arithmetic number, because the mean of its divisors is an integer number (145160311).

Almost surely, 2^290320621 is an apocalyptic number.

It is an amenable number.

290320621 is a deficient number, since it is larger than the sum of its proper divisors (1).

290320621 is an equidigital number, since it uses as much as digits as its factorization.

290320621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 290320621 is about 17038.7975221258. The cubic root of 290320621 is about 662.1544387963.

The spelling of 290320621 in words is "two hundred ninety million, three hundred twenty thousand, six hundred twenty-one".