1202651981 has 2 divisors, whose sum is σ = 1202651982. Its totient is φ = 1202651980.

The previous prime is 1202651977. The next prime is 1202652001. The reversal of 1202651981 is 1891562021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1007491081 + 195160900 = 31741^2 + 13970^2 .

It is a cyclic number.

It is not a de Polignac number, because 1202651981 - 2² = 1202651977 is a prime.

It is a super-2 number, since 2×1202651981² = 2892743574806448722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1202651921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 601325990 + 601325991.

It is an arithmetic number, because the mean of its divisors is an integer number (601325991).

Almost surely, 2^1202651981 is an apocalyptic number.

It is an amenable number.

1202651981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1202651981 is an equidigital number, since it uses as much as digits as its factorization.

1202651981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 1202651981 is about 34679.2730748498. The cubic root of 1202651981 is about 1063.4408127542.

The spelling of 1202651981 in words is "one billion, two hundred two million, six hundred fifty-one thousand, nine hundred eighty-one".