87128469 has 12 divisors (see below), whose sum is σ = 126025900. Its totient is φ = 58005504.

The previous prime is 87128467. The next prime is 87128473. The reversal of 87128469 is 96482178.

It can be written as a sum of positive squares in 2 ways, for example, as 18818244 + 68310225 = 4338^2 + 8265^2 .

It is not a de Polignac number, because 87128469 - 2¹ = 87128467 is a prime.

It is a super-2 number, since 2×87128469² = 15182740220567922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87128467) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 627 + ... + 13215.

Almost surely, 2^87128469 is an apocalyptic number.

It is an amenable number.

87128469 is a deficient number, since it is larger than the sum of its proper divisors (38897431).

87128469 is a wasteful number, since it uses less digits than its factorization.

87128469 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13364 (or 13361 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 87128469 is about 9334.2631739200. The cubic root of 87128469 is about 443.3227592154.

The spelling of 87128469 in words is "eighty-seven million, one hundred twenty-eight thousand, four hundred sixty-nine".