126021520 has 20 divisors (see below), whose sum is σ = 293000220. Its totient is φ = 50408576.

The previous prime is 126021503. The next prime is 126021529. The reversal of 126021520 is 25120621.

It can be written as a sum of positive squares in 2 ways, for example, as 91164304 + 34857216 = 9548^2 + 5904^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×126021520² = 31762847006220800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (126021529) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 787555 + ... + 787714.

It is an arithmetic number, because the mean of its divisors is an integer number (14650011).

Almost surely, 2^126021520 is an apocalyptic number.

126021520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

126021520 is an abundant number, since it is smaller than the sum of its proper divisors (166978700).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

126021520 is a wasteful number, since it uses less digits than its factorization.

126021520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1575282 (or 1575276 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 126021520 is about 11225.9306963833. The cubic root of 126021520 is about 501.3583331869.

The spelling of 126021520 in words is "one hundred twenty-six million, twenty-one thousand, five hundred twenty".