1246721121 has 6 divisors (see below), whose sum is σ = 1800819410. Its totient is φ = 831147408.

The previous prime is 1246721117. The next prime is 1246721123. The reversal of 1246721121 is 1211276421.

It can be written as a sum of positive squares in only one way, i.e., 980378721 + 266342400 = 31311^2 + 16320^2 .

It is not a de Polignac number, because 1246721121 - 2² = 1246721117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1246721123) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 69262276 + ... + 69262293.

Almost surely, 2^1246721121 is an apocalyptic number.

It is an amenable number.

1246721121 is a deficient number, since it is larger than the sum of its proper divisors (554098289).

1246721121 is a wasteful number, since it uses less digits than its factorization.

1246721121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138524575 (or 138524572 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 1246721121 is about 35308.9382593133. The cubic root of 1246721121 is about 1076.2746361724.

Adding to 1246721121 its reverse (1211276421), we get a palindrome (2457997542).

The spelling of 1246721121 in words is "one billion, two hundred forty-six million, seven hundred twenty-one thousand, one hundred twenty-one".