87123553 has 4 divisors (see below), whose sum is σ = 95043888. Its totient is φ = 79203220.

The previous prime is 87123541. The next prime is 87123559. The reversal of 87123553 is 35532178.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 87123553 - 2⁹ = 87123041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87123559) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3960151 + ... + 3960172.

It is an arithmetic number, because the mean of its divisors is an integer number (23760972).

Almost surely, 2^87123553 is an apocalyptic number.

It is an amenable number.

87123553 is a deficient number, since it is larger than the sum of its proper divisors (7920335).

87123553 is a wasteful number, since it uses less digits than its factorization.

87123553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7920334.

The product of its digits is 25200, while the sum is 34.

The square root of 87123553 is about 9333.9998392972. Note that the first 3 decimals coincide. The cubic root of 87123553 is about 443.3144212760.

It can be divided in two parts, 8 and 7123553, that added together give a square (7123561 = 2669²).

The spelling of 87123553 in words is "eighty-seven million, one hundred twenty-three thousand, five hundred fifty-three".