126535021 has 4 divisors (see below), whose sum is σ = 127092672. Its totient is φ = 125977372.

The previous prime is 126535007. The next prime is 126535037. The reversal of 126535021 is 120535621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120535621 = 53 ⋅2274257.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-126535021 is a prime.

It is a super-2 number, since 2×126535021² = 32022223078940882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126535081) 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, 278485 + ... + 278938.

It is an arithmetic number, because the mean of its divisors is an integer number (31773168).

Almost surely, 2^126535021 is an apocalyptic number.

It is an amenable number.

126535021 is a deficient number, since it is larger than the sum of its proper divisors (557651).

126535021 is an equidigital number, since it uses as much as digits as its factorization.

126535021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557650.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 126535021 is about 11248.7786448130. The cubic root of 126535021 is about 502.0383734416.

The spelling of 126535021 in words is "one hundred twenty-six million, five hundred thirty-five thousand, twenty-one".