87211988 has 12 divisors (see below), whose sum is σ = 152978112. Its totient is φ = 43503960.

The previous prime is 87211981. The next prime is 87211991. The reversal of 87211988 is 88911278.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87211981) 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, 23570 + ... + 27017.

It is an arithmetic number, because the mean of its divisors is an integer number (12748176).

Almost surely, 2^87211988 is an apocalyptic number.

It is an amenable number.

87211988 is a deficient number, since it is larger than the sum of its proper divisors (65766124).

87211988 is a wasteful number, since it uses less digits than its factorization.

87211988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51022 (or 51020 counting only the distinct ones).

The product of its digits is 64512, while the sum is 44.

The square root of 87211988 is about 9338.7358887592. The cubic root of 87211988 is about 443.4643663907.

The spelling of 87211988 in words is "eighty-seven million, two hundred eleven thousand, nine hundred eighty-eight".