1206404561 has 2 divisors, whose sum is σ = 1206404562. Its totient is φ = 1206404560.

The previous prime is 1206404519. The next prime is 1206404567. The reversal of 1206404561 is 1654046021.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1161514561 + 44890000 = 34081^2 + 6700^2 .

It is a cyclic number.

It is not a de Polignac number, because 1206404561 - 2²⁶ = 1139295697 is a prime.

It is not a weakly prime, because it can be changed into another prime (1206404567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 603202280 + 603202281.

It is an arithmetic number, because the mean of its divisors is an integer number (603202281).

Almost surely, 2^1206404561 is an apocalyptic number.

It is an amenable number.

1206404561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1206404561 is an equidigital number, since it uses as much as digits as its factorization.

1206404561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 1206404561 is about 34733.3350111964. The cubic root of 1206404561 is about 1064.5457329243.

The spelling of 1206404561 in words is "one billion, two hundred six million, four hundred four thousand, five hundred sixty-one".