87211813 has 8 divisors (see below), whose sum is σ = 95110400. Its totient is φ = 79483248.

The previous prime is 87211807. The next prime is 87211841. The reversal of 87211813 is 31811278.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 87211813 - 2¹³ = 87203621 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 (87211013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41433 + ... + 43486.

It is an arithmetic number, because the mean of its divisors is an integer number (11888800).

Almost surely, 2^87211813 is an apocalyptic number.

It is an amenable number.

87211813 is a deficient number, since it is larger than the sum of its proper divisors (7898587).

87211813 is a wasteful number, since it uses less digits than its factorization.

87211813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85011.

The product of its digits is 2688, while the sum is 31.

The square root of 87211813 is about 9338.7265191781. The cubic root of 87211813 is about 443.4640697713.

The spelling of 87211813 in words is "eighty-seven million, two hundred eleven thousand, eight hundred thirteen".