1981962061 has 2 divisors, whose sum is σ = 1981962062. Its totient is φ = 1981962060.

The previous prime is 1981962019. The next prime is 1981962071. The reversal of 1981962061 is 1602691891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1286585161 + 695376900 = 35869^2 + 26370^2 .

It is an emirp because it is prime and its reverse (1602691891) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1981962061 is a prime.

It is a super-2 number, since 2×1981962061² = 7856347222486735442, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1981961999 and 1981962017.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1981962071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 990981030 + 990981031.

It is an arithmetic number, because the mean of its divisors is an integer number (990981031).

Almost surely, 2^1981962061 is an apocalyptic number.

It is an amenable number.

1981962061 is a deficient number, since it is larger than the sum of its proper divisors (1).

1981962061 is an equidigital number, since it uses as much as digits as its factorization.

1981962061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 43.

The square root of 1981962061 is about 44519.2324843994. The cubic root of 1981962061 is about 1256.1218755134.

The spelling of 1981962061 in words is "one billion, nine hundred eighty-one million, nine hundred sixty-two thousand, sixty-one".