87644261 has 2 divisors, whose sum is σ = 87644262. Its totient is φ = 87644260.

The previous prime is 87644257. The next prime is 87644273. The reversal of 87644261 is 16244678.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50495236 + 37149025 = 7106^2 + 6095^2 .

It is a cyclic number.

It is not a de Polignac number, because 87644261 - 2² = 87644257 is a prime.

It is a super-2 number, since 2×87644261² = 15363032972472242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87644461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43822130 + 43822131.

It is an arithmetic number, because the mean of its divisors is an integer number (43822131).

Almost surely, 2^87644261 is an apocalyptic number.

It is an amenable number.

87644261 is a deficient number, since it is larger than the sum of its proper divisors (1).

87644261 is an equidigital number, since it uses as much as digits as its factorization.

87644261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 38.

The square root of 87644261 is about 9361.8513660493. The cubic root of 87644261 is about 444.1958477090.

The spelling of 87644261 in words is "eighty-seven million, six hundred forty-four thousand, two hundred sixty-one".