126721806 has 16 divisors (see below), whose sum is σ = 254257104. Its totient is φ = 42105024.

The previous prime is 126721801. The next prime is 126721813. The reversal of 126721806 is 608127621.

It is a super-2 number, since 2×126721806² = 32116832231803272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126721801) 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, 31861 + ... + 35616.

It is an arithmetic number, because the mean of its divisors is an integer number (15891069).

Almost surely, 2^126721806 is an apocalyptic number.

126721806 is an abundant number, since it is smaller than the sum of its proper divisors (127535298).

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

126721806 is a wasteful number, since it uses less digits than its factorization.

126721806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67795.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 126721806 is about 11257.0780400600. The cubic root of 126721806 is about 502.2852804071.

The spelling of 126721806 in words is "one hundred twenty-six million, seven hundred twenty-one thousand, eight hundred six".