87261562691 has 2 divisors, whose sum is σ = 87261562692. Its totient is φ = 87261562690.

The previous prime is 87261562679. The next prime is 87261562757. The reversal of 87261562691 is 19626516278.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87261562691 is a prime.

It is a super-2 number, since 2×87261562691² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (87261562631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43630781345 + 43630781346.

It is an arithmetic number, because the mean of its divisors is an integer number (43630781346).

Almost surely, 2^87261562691 is an apocalyptic number.

87261562691 is a deficient number, since it is larger than the sum of its proper divisors (1).

87261562691 is an equidigital number, since it uses as much as digits as its factorization.

87261562691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2177280, while the sum is 53.

The spelling of 87261562691 in words is "eighty-seven billion, two hundred sixty-one million, five hundred sixty-two thousand, six hundred ninety-one".