1521391229 has 2 divisors, whose sum is σ = 1521391230. Its totient is φ = 1521391228.

The previous prime is 1521391219. The next prime is 1521391231. The reversal of 1521391229 is 9221931251.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1521156004 + 235225 = 39002^2 + 485^2 .

It is a cyclic number.

It is not a de Polignac number, because 1521391229 - 2²⁸ = 1252955773 is a prime.

Together with 1521391231, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1521391219) 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, 760695614 + 760695615.

It is an arithmetic number, because the mean of its divisors is an integer number (760695615).

Almost surely, 2^1521391229 is an apocalyptic number.

It is an amenable number.

1521391229 is a deficient number, since it is larger than the sum of its proper divisors (1).

1521391229 is an equidigital number, since it uses as much as digits as its factorization.

1521391229 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9720, while the sum is 35.

The square root of 1521391229 is about 39005.0154339157. The cubic root of 1521391229 is about 1150.1300997110.

The spelling of 1521391229 in words is "one billion, five hundred twenty-one million, three hundred ninety-one thousand, two hundred twenty-nine".