126521549 has 8 divisors (see below), whose sum is σ = 157741248. Its totient is φ = 98588160.

The previous prime is 126521543. The next prime is 126521557. The reversal of 126521549 is 945125621.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 126521549 - 2²⁰ = 125472973 is a prime.

It is a super-2 number, since 2×126521549² = 32015404722718802, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126521543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 821492 + ... + 821645.

It is an arithmetic number, because the mean of its divisors is an integer number (19717656).

Almost surely, 2^126521549 is an apocalyptic number.

It is an amenable number.

126521549 is a deficient number, since it is larger than the sum of its proper divisors (31219699).

126521549 is a wasteful number, since it uses less digits than its factorization.

126521549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1643155.

The product of its digits is 21600, while the sum is 35.

The square root of 126521549 is about 11248.1798083068. The cubic root of 126521549 is about 502.0205557103.

The spelling of 126521549 in words is "one hundred twenty-six million, five hundred twenty-one thousand, five hundred forty-nine".