220406162521 has 2 divisors, whose sum is σ = 220406162522. Its totient is φ = 220406162520.

The previous prime is 220406162461. The next prime is 220406162597. The reversal of 220406162521 is 125261604022.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 205286017225 + 15120145296 = 453085^2 + 122964^2 .

It is a cyclic number.

It is not a de Polignac number, because 220406162521 - 2⁷ = 220406162393 is a prime.

It is not a weakly prime, because it can be changed into another prime (220406162321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110203081260 + 110203081261.

It is an arithmetic number, because the mean of its divisors is an integer number (110203081261).

Almost surely, 2^220406162521 is an apocalyptic number.

It is an amenable number.

220406162521 is a deficient number, since it is larger than the sum of its proper divisors (1).

220406162521 is an equidigital number, since it uses as much as digits as its factorization.

220406162521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11520, while the sum is 31.

Adding to 220406162521 its reverse (125261604022), we get a palindrome (345667766543).

The spelling of 220406162521 in words is "two hundred twenty billion, four hundred six million, one hundred sixty-two thousand, five hundred twenty-one".