1206736921 has 4 divisors (see below), whose sum is σ = 1299562852. Its totient is φ = 1113910992.

The previous prime is 1206736901. The next prime is 1206736997. The reversal of 1206736921 is 1296376021.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1296376021 = 17 ⋅76257413.

It can be written as a sum of positive squares in 2 ways, for example, as 345960000 + 860776921 = 18600^2 + 29339^2 .

It is a cyclic number.

It is not a de Polignac number, because 1206736921 - 2⁵ = 1206736889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1206736901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46412946 + ... + 46412971.

It is an arithmetic number, because the mean of its divisors is an integer number (324890713).

Almost surely, 2^1206736921 is an apocalyptic number.

It is an amenable number.

1206736921 is a deficient number, since it is larger than the sum of its proper divisors (92825931).

1206736921 is an equidigital number, since it uses as much as digits as its factorization.

1206736921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92825930.

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 1206736921 is about 34738.1191344609. The cubic root of 1206736921 is about 1064.6434834205.

The spelling of 1206736921 in words is "one billion, two hundred six million, seven hundred thirty-six thousand, nine hundred twenty-one".