287061391 has 2 divisors, whose sum is σ = 287061392. Its totient is φ = 287061390.

The previous prime is 287061361. The next prime is 287061407. The reversal of 287061391 is 193160782.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 287061391 - 2¹³ = 287053199 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 287061391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (287061361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 143530695 + 143530696.

It is an arithmetic number, because the mean of its divisors is an integer number (143530696).

Almost surely, 2^287061391 is an apocalyptic number.

287061391 is a deficient number, since it is larger than the sum of its proper divisors (1).

287061391 is an equidigital number, since it uses as much as digits as its factorization.

287061391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 287061391 is about 16942.8861472891. The cubic root of 287061391 is about 659.6672572817.

It can be divided in two parts, 2870 and 61391, that added together give a triangular number (64261 = T₃₅₈).

The spelling of 287061391 in words is "two hundred eighty-seven million, sixty-one thousand, three hundred ninety-one".