126991081 has 8 divisors (see below), whose sum is σ = 147512384. Its totient is φ = 107064720.

The previous prime is 126991031. The next prime is 126991091. The reversal of 126991081 is 180199621.

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

It is a de Polignac number, because none of the positive numbers 2^k-126991081 is a prime.

It is a super-2 number, since 2×126991081² = 32253469307097122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 126991081.

It is not an unprimeable number, because it can be changed into a prime (126991031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 148275 + ... + 149128.

It is an arithmetic number, because the mean of its divisors is an integer number (18439048).

Almost surely, 2^126991081 is an apocalyptic number.

It is an amenable number.

126991081 is a deficient number, since it is larger than the sum of its proper divisors (20521303).

126991081 is an equidigital number, since it uses as much as digits as its factorization.

126991081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297471.

The product of its (nonzero) digits is 7776, while the sum is 37.

The square root of 126991081 is about 11269.0319460014. The cubic root of 126991081 is about 502.6408024363.

The spelling of 126991081 in words is "one hundred twenty-six million, nine hundred ninety-one thousand, eighty-one".