2187040981 has 2 divisors, whose sum is σ = 2187040982. Its totient is φ = 2187040980.

The previous prime is 2187040967. The next prime is 2187041009. The reversal of 2187040981 is 1890407812.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1954966225 + 232074756 = 44215^2 + 15234^2 .

It is a cyclic number.

It is not a de Polignac number, because 2187040981 - 2⁵ = 2187040949 is a prime.

It is a super-2 number, since 2×2187040981² = 9566296505146884722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2187040181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1093520490 + 1093520491.

It is an arithmetic number, because the mean of its divisors is an integer number (1093520491).

Almost surely, 2^2187040981 is an apocalyptic number.

It is an amenable number.

2187040981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2187040981 is an equidigital number, since it uses as much as digits as its factorization.

2187040981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 40.

The square root of 2187040981 is about 46765.8099577031. The cubic root of 2187040981 is about 1298.0327208844.

The spelling of 2187040981 in words is "two billion, one hundred eighty-seven million, forty thousand, nine hundred eighty-one".