126991265 has 8 divisors (see below), whose sum is σ = 152516520. Its totient is φ = 101508352.

The previous prime is 126991223. The next prime is 126991297. The reversal of 126991265 is 562199621.

It can be written as a sum of positive squares in 4 ways, for example, as 49392784 + 77598481 = 7028^2 + 8809^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 126991265 - 2²⁶ = 59882401 is a prime.

It is a super-2 number, since 2×126991265² = 32253562772600450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3560 + ... + 16329.

It is an arithmetic number, because the mean of its divisors is an integer number (19064565).

Almost surely, 2^126991265 is an apocalyptic number.

It is an amenable number.

126991265 is a deficient number, since it is larger than the sum of its proper divisors (25525255).

126991265 is a wasteful number, since it uses less digits than its factorization.

126991265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21171.

The product of its digits is 58320, while the sum is 41.

The square root of 126991265 is about 11269.0401099650. The cubic root of 126991265 is about 502.6410451984.

The spelling of 126991265 in words is "one hundred twenty-six million, nine hundred ninety-one thousand, two hundred sixty-five".