1246866721 has 3 divisors (see below), whose sum is σ = 1246902033. Its totient is φ = 1246831410.

The previous prime is 1246866689. The next prime is 1246866763. The reversal of 1246866721 is 1276686421.

The square root of 1246866721 is 35311.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1276686421 = 13121 ⋅97301.

It is not a de Polignac number, because 1246866721 - 2⁵ = 1246866689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1246866821) 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 2 ways as a sum of consecutive naturals, for example, 17656 + ... + 52966.

It is an arithmetic number, because the mean of its divisors is an integer number (415634011).

Almost surely, 2^1246866721 is an apocalyptic number.

1246866721 is the 35311-st square number.

1246866721 is the 17656-th centered octagonal number.

It is an amenable number.

1246866721 is a deficient number, since it is larger than the sum of its proper divisors (35312).

1246866721 is an frugal number, since it uses more digits than its factorization.

1246866721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70622 (or 35311 counting only the distinct ones).

The product of its digits is 193536, while the sum is 43.

The cubic root of 1246866721 is about 1076.3165326009.

The spelling of 1246866721 in words is "one billion, two hundred forty-six million, eight hundred sixty-six thousand, seven hundred twenty-one".