1205370721 has 2 divisors, whose sum is σ = 1205370722. Its totient is φ = 1205370720.

The previous prime is 1205370713. The next prime is 1205370739. The reversal of 1205370721 is 1270735021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 650250000 + 555120721 = 25500^2 + 23561^2 .

It is a cyclic number.

It is not a de Polignac number, because 1205370721 - 2³ = 1205370713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1205370721.

It is not a weakly prime, because it can be changed into another prime (1205370121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602685360 + 602685361.

It is an arithmetic number, because the mean of its divisors is an integer number (602685361).

Almost surely, 2^1205370721 is an apocalyptic number.

It is an amenable number.

1205370721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1205370721 is an equidigital number, since it uses as much as digits as its factorization.

1205370721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 1205370721 is about 34718.4492885267. The cubic root of 1205370721 is about 1064.2415551144.

The spelling of 1205370721 in words is "one billion, two hundred five million, three hundred seventy thousand, seven hundred twenty-one".