16125521 has 2 divisors, whose sum is σ = 16125522. Its totient is φ = 16125520.

The previous prime is 16125517. The next prime is 16125523. The reversal of 16125521 is 12552161.

16125521 = 2839² + 2840².

It is a happy number.

16125521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8065600 + 8059921 = 2840^2 + 2839^2 .

It is a cyclic number.

It is not a de Polignac number, because 16125521 - 2² = 16125517 is a prime.

Together with 16125523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16125523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8062760 + 8062761.

It is an arithmetic number, because the mean of its divisors is an integer number (8062761).

Almost surely, 2^16125521 is an apocalyptic number.

16125521 is the 2840-th centered square number.

It is an amenable number.

16125521 is a deficient number, since it is larger than the sum of its proper divisors (1).

16125521 is an equidigital number, since it uses as much as digits as its factorization.

16125521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 600, while the sum is 23.

The square root of 16125521 is about 4015.6594726147. The cubic root of 16125521 is about 252.6414382566.

Adding to 16125521 its reverse (12552161), we get a palindrome (28677682).

The spelling of 16125521 in words is "sixteen million, one hundred twenty-five thousand, five hundred twenty-one".