126555521 has 2 divisors, whose sum is σ = 126555522. Its totient is φ = 126555520.

The previous prime is 126555509. The next prime is 126555553. The reversal of 126555521 is 125555621.

It is an a-pointer prime, because the next prime (126555553) can be obtained adding 126555521 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 108160000 + 18395521 = 10400^2 + 4289^2 .

It is an emirp because it is prime and its reverse (125555621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 126555521 - 2¹⁴ = 126539137 is a prime.

It is a super-3 number, since 3×126555521³ (a number of 25 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (126555571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63277760 + 63277761.

It is an arithmetic number, because the mean of its divisors is an integer number (63277761).

Almost surely, 2^126555521 is an apocalyptic number.

It is an amenable number.

126555521 is a deficient number, since it is larger than the sum of its proper divisors (1).

126555521 is an equidigital number, since it uses as much as digits as its factorization.

126555521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15000, while the sum is 32.

The square root of 126555521 is about 11249.6898179461. The cubic root of 126555521 is about 502.0654838042.

The spelling of 126555521 in words is "one hundred twenty-six million, five hundred fifty-five thousand, five hundred twenty-one".