1205753921 has 4 divisors (see below), whose sum is σ = 1222271172. Its totient is φ = 1189236672.

The previous prime is 1205753903. The next prime is 1205753981. The reversal of 1205753921 is 1293575021.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 920515600 + 285238321 = 30340^2 + 16889^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1205753921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1205753981) 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, 8258516 + ... + 8258661.

It is an arithmetic number, because the mean of its divisors is an integer number (305567793).

Almost surely, 2^1205753921 is an apocalyptic number.

It is an amenable number.

1205753921 is a deficient number, since it is larger than the sum of its proper divisors (16517251).

1205753921 is an equidigital number, since it uses as much as digits as its factorization.

1205753921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16517250.

The product of its (nonzero) digits is 18900, while the sum is 35.

The square root of 1205753921 is about 34723.9675296473. The cubic root of 1205753921 is about 1064.3543210178.

The spelling of 1205753921 in words is "one billion, two hundred five million, seven hundred fifty-three thousand, nine hundred twenty-one".