2115650981 has 2 divisors, whose sum is σ = 2115650982. Its totient is φ = 2115650980.

The previous prime is 2115650959. The next prime is 2115651053. The reversal of 2115650981 is 1890565112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1278706081 + 836944900 = 35759^2 + 28930^2 .

It is a cyclic number.

It is not a de Polignac number, because 2115650981 - 2¹⁸ = 2115388837 is a prime.

It is a super-2 number, since 2×2115650981² = 8951958146812524722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2115650921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1057825490 + 1057825491.

It is an arithmetic number, because the mean of its divisors is an integer number (1057825491).

Almost surely, 2^2115650981 is an apocalyptic number.

It is an amenable number.

2115650981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2115650981 is an equidigital number, since it uses as much as digits as its factorization.

2115650981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 38.

The square root of 2115650981 is about 45996.2061587692. The cubic root of 2115650981 is about 1283.7526149128.

The spelling of 2115650981 in words is "two billion, one hundred fifteen million, six hundred fifty thousand, nine hundred eighty-one".