126738721 has 8 divisors (see below), whose sum is σ = 134262080. Its totient is φ = 119300688.

The previous prime is 126738709. The next prime is 126738793. The reversal of 126738721 is 127837621.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-126738721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126732721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18261 + ... + 24226.

It is an arithmetic number, because the mean of its divisors is an integer number (16782760).

Almost surely, 2^126738721 is an apocalyptic number.

It is an amenable number.

126738721 is a deficient number, since it is larger than the sum of its proper divisors (7523359).

126738721 is a wasteful number, since it uses less digits than its factorization.

126738721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42663.

The product of its digits is 28224, while the sum is 37.

The square root of 126738721 is about 11257.8293200776. The cubic root of 126738721 is about 502.3076279882.

The spelling of 126738721 in words is "one hundred twenty-six million, seven hundred thirty-eight thousand, seven hundred twenty-one".