641646469 has 2 divisors, whose sum is σ = 641646470. Its totient is φ = 641646468.

The previous prime is 641646457. The next prime is 641646493. The reversal of 641646469 is 964646146.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 454968900 + 186677569 = 21330^2 + 13663^2 .

It is a cyclic number.

It is not a de Polignac number, because 641646469 - 2⁵ = 641646437 is a prime.

It is a super-2 number, since 2×641646469² = 823420382360335922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641646409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320823234 + 320823235.

It is an arithmetic number, because the mean of its divisors is an integer number (320823235).

Almost surely, 2^641646469 is an apocalyptic number.

It is an amenable number.

641646469 is a deficient number, since it is larger than the sum of its proper divisors (1).

641646469 is an equidigital number, since it uses as much as digits as its factorization.

641646469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 746496, while the sum is 46.

The square root of 641646469 is about 25330.7415801433. The cubic root of 641646469 is about 862.5122452648.

The spelling of 641646469 in words is "six hundred forty-one million, six hundred forty-six thousand, four hundred sixty-nine".