87922981 has 2 divisors, whose sum is σ = 87922982. Its totient is φ = 87922980.

The previous prime is 87922973. The next prime is 87922993. The reversal of 87922981 is 18922978.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84916225 + 3006756 = 9215^2 + 1734^2 .

It is a cyclic number.

It is not a de Polignac number, because 87922981 - 2³ = 87922973 is a prime.

It is a super-2 number, since 2×87922981² = 15460901175852722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87922781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43961490 + 43961491.

It is an arithmetic number, because the mean of its divisors is an integer number (43961491).

Almost surely, 2^87922981 is an apocalyptic number.

It is an amenable number.

87922981 is a deficient number, since it is larger than the sum of its proper divisors (1).

87922981 is an equidigital number, since it uses as much as digits as its factorization.

87922981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 46.

The square root of 87922981 is about 9376.7254945423. The cubic root of 87922981 is about 444.6662160544. Note that the first 3 decimals are identical.

The spelling of 87922981 in words is "eighty-seven million, nine hundred twenty-two thousand, nine hundred eighty-one".