87131444 has 6 divisors (see below), whose sum is σ = 152480034. Its totient is φ = 43565720.

The previous prime is 87131441. The next prime is 87131449. The reversal of 87131444 is 44413178.

It can be written as a sum of positive squares in only one way, i.e., 78499600 + 8631844 = 8860^2 + 2938^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 87131444.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87131441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10891427 + ... + 10891434.

It is an arithmetic number, because the mean of its divisors is an integer number (25413339).

Almost surely, 2^87131444 is an apocalyptic number.

It is an amenable number.

87131444 is a deficient number, since it is larger than the sum of its proper divisors (65348590).

87131444 is a wasteful number, since it uses less digits than its factorization.

87131444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21782865 (or 21782863 counting only the distinct ones).

The product of its digits is 10752, while the sum is 32.

The square root of 87131444 is about 9334.4225316835. The cubic root of 87131444 is about 443.3278049072.

The spelling of 87131444 in words is "eighty-seven million, one hundred thirty-one thousand, four hundred forty-four".