221501429 has 2 divisors, whose sum is σ = 221501430. Its totient is φ = 221501428.

The previous prime is 221501387. The next prime is 221501453. The reversal of 221501429 is 924105122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 185776900 + 35724529 = 13630^2 + 5977^2 .

It is a cyclic number.

It is not a de Polignac number, because 221501429 - 2¹² = 221497333 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221501398 and 221501407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221501629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110750714 + 110750715.

It is an arithmetic number, because the mean of its divisors is an integer number (110750715).

Almost surely, 2^221501429 is an apocalyptic number.

It is an amenable number.

221501429 is a deficient number, since it is larger than the sum of its proper divisors (1).

221501429 is an equidigital number, since it uses as much as digits as its factorization.

221501429 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 221501429 is about 14882.9240742537. The cubic root of 221501429 is about 605.0512708410.

The spelling of 221501429 in words is "two hundred twenty-one million, five hundred one thousand, four hundred twenty-nine".