87138397 has 4 divisors (see below), whose sum is σ = 87164896. Its totient is φ = 87111900.

The previous prime is 87138377. The next prime is 87138431. The reversal of 87138397 is 79383178.

It is a happy number.

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 87138397 - 2⁷ = 87138269 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87138347) 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, 7479 + ... + 15172.

It is an arithmetic number, because the mean of its divisors is an integer number (21791224).

Almost surely, 2^87138397 is an apocalyptic number.

It is an amenable number.

87138397 is a deficient number, since it is larger than the sum of its proper divisors (26499).

87138397 is a wasteful number, since it uses less digits than its factorization.

87138397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26498.

The product of its digits is 254016, while the sum is 46.

The square root of 87138397 is about 9334.7949629330. The cubic root of 87138397 is about 443.3395969618.

The spelling of 87138397 in words is "eighty-seven million, one hundred thirty-eight thousand, three hundred ninety-seven".