87742789 has 2 divisors, whose sum is σ = 87742790. Its totient is φ = 87742788.

The previous prime is 87742751. The next prime is 87742793. The reversal of 87742789 is 98724778.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87048900 + 693889 = 9330^2 + 833^2 .

It is a cyclic number.

It is not a de Polignac number, because 87742789 - 2¹³ = 87734597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87742289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43871394 + 43871395.

It is an arithmetic number, because the mean of its divisors is an integer number (43871395).

Almost surely, 2^87742789 is an apocalyptic number.

It is an amenable number.

87742789 is a deficient number, since it is larger than the sum of its proper divisors (1).

87742789 is an equidigital number, since it uses as much as digits as its factorization.

87742789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1580544, while the sum is 52.

The square root of 87742789 is about 9367.1120949842. The cubic root of 87742789 is about 444.3622375293.

The spelling of 87742789 in words is "eighty-seven million, seven hundred forty-two thousand, seven hundred eighty-nine".