87291649 has 3 divisors (see below), whose sum is σ = 87300993. Its totient is φ = 87282306.

The previous prime is 87291641. The next prime is 87291661. The reversal of 87291649 is 94619278.

The square root of 87291649 is 9343.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 87291649 - 2³ = 87291641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 87291599 and 87291608.

It is not an unprimeable number, because it can be changed into a prime (87291641) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 4672 + ... + 14014.

It is an arithmetic number, because the mean of its divisors is an integer number (29100331).

Almost surely, 2^87291649 is an apocalyptic number.

87291649 is the 9343-rd square number.

87291649 is the 4672-nd centered octagonal number.

It is an amenable number.

87291649 is a deficient number, since it is larger than the sum of its proper divisors (9344).

87291649 is an frugal number, since it uses more digits than its factorization.

87291649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18686 (or 9343 counting only the distinct ones).

The product of its digits is 217728, while the sum is 46.

The cubic root of 87291649 is about 443.5993480796.

The spelling of 87291649 in words is "eighty-seven million, two hundred ninety-one thousand, six hundred forty-nine".