126720051 has 4 divisors (see below), whose sum is σ = 168960072. Its totient is φ = 84480032.

The previous prime is 126720031. The next prime is 126720067. The reversal of 126720051 is 150027621.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 126720051 - 2²⁶ = 59611187 is a prime.

It is not an unprimeable number, because it can be changed into a prime (126720031) 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, 21120006 + ... + 21120011.

It is an arithmetic number, because the mean of its divisors is an integer number (42240018).

Almost surely, 2^126720051 is an apocalyptic number.

126720051 is a deficient number, since it is larger than the sum of its proper divisors (42240021).

126720051 is an equidigital number, since it uses as much as digits as its factorization.

126720051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42240020.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 126720051 is about 11257.0000888336. Note that the first 4 decimals coincide. The cubic root of 126720051 is about 502.2829616408.

Adding to 126720051 its reverse (150027621), we get a palindrome (276747672).

The spelling of 126720051 in words is "one hundred twenty-six million, seven hundred twenty thousand, fifty-one".