1201566101 has 2 divisors, whose sum is σ = 1201566102. Its totient is φ = 1201566100.

The previous prime is 1201566097. The next prime is 1201566109. The reversal of 1201566101 is 1016651021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 728460100 + 473106001 = 26990^2 + 21751^2 .

It is a cyclic number.

It is not a de Polignac number, because 1201566101 - 2² = 1201566097 is a prime.

It is a super-2 number, since 2×1201566101² = 2887522190144684402, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1201566109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 600783050 + 600783051.

It is an arithmetic number, because the mean of its divisors is an integer number (600783051).

Almost surely, 2^1201566101 is an apocalyptic number.

It is an amenable number.

1201566101 is a deficient number, since it is larger than the sum of its proper divisors (1).

1201566101 is an equidigital number, since it uses as much as digits as its factorization.

1201566101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 23.

The square root of 1201566101 is about 34663.6135017687. The cubic root of 1201566101 is about 1063.1206545119.

The spelling of 1201566101 in words is "one billion, two hundred one million, five hundred sixty-six thousand, one hundred one".