87121903 has 4 divisors (see below), whose sum is σ = 95042088. Its totient is φ = 79201720.

The previous prime is 87121901. The next prime is 87121927. The reversal of 87121903 is 30912178.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 87121903 - 2¹ = 87121901 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87121901) 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, 3960076 + ... + 3960097.

It is an arithmetic number, because the mean of its divisors is an integer number (23760522).

Almost surely, 2^87121903 is an apocalyptic number.

87121903 is a deficient number, since it is larger than the sum of its proper divisors (7920185).

87121903 is a wasteful number, since it uses less digits than its factorization.

87121903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7920184.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 87121903 is about 9333.9114523334. The cubic root of 87121903 is about 443.3116226703.

The spelling of 87121903 in words is "eighty-seven million, one hundred twenty-one thousand, nine hundred three".