84739987 has 2 divisors, whose sum is σ = 84739988. Its totient is φ = 84739986.

The previous prime is 84739973. The next prime is 84739997. The reversal of 84739987 is 78993748.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-84739987 is a prime.

It is not a weakly prime, because it can be changed into another prime (84739997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42369993 + 42369994.

It is an arithmetic number, because the mean of its divisors is an integer number (42369994).

Almost surely, 2^84739987 is an apocalyptic number.

84739987 is a deficient number, since it is larger than the sum of its proper divisors (1).

84739987 is an equidigital number, since it uses as much as digits as its factorization.

84739987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3048192, while the sum is 55.

The square root of 84739987 is about 9205.4324721873. The cubic root of 84739987 is about 439.2341826801.

The spelling of 84739987 in words is "eighty-four million, seven hundred thirty-nine thousand, nine hundred eighty-seven".