502405661 has 2 divisors, whose sum is σ = 502405662. Its totient is φ = 502405660.

The previous prime is 502405643. The next prime is 502405681. The reversal of 502405661 is 166504205.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 480968761 + 21436900 = 21931^2 + 4630^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-502405661 is a prime.

It is a super-2 number, since 2×502405661² = 504822896409693842, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (502405621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 251202830 + 251202831.

It is an arithmetic number, because the mean of its divisors is an integer number (251202831).

Almost surely, 2^502405661 is an apocalyptic number.

It is an amenable number.

502405661 is a deficient number, since it is larger than the sum of its proper divisors (1).

502405661 is an equidigital number, since it uses as much as digits as its factorization.

502405661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 502405661 is about 22414.4074425357. The cubic root of 502405661 is about 794.9714062208.

Adding to 502405661 its reverse (166504205), we get a palindrome (668909866).

The spelling of 502405661 in words is "five hundred two million, four hundred five thousand, six hundred sixty-one".