861356493 has 12 divisors (see below), whose sum is σ = 1317368988. Its totient is φ = 540458880.

The previous prime is 861356473. The next prime is 861356519. The reversal of 861356493 is 394653168.

861356493 is a `hidden beast` number, since 86 + 1 + 3 + 564 + 9 + 3 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 435223044 + 426133449 = 20862^2 + 20643^2 .

It is not a de Polignac number, because 861356493 - 2⁶ = 861356429 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861356423) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2814738 + ... + 2815043.

It is an arithmetic number, because the mean of its divisors is an integer number (109780749).

Almost surely, 2^861356493 is an apocalyptic number.

It is an amenable number.

861356493 is a deficient number, since it is larger than the sum of its proper divisors (456012495).

861356493 is a wasteful number, since it uses less digits than its factorization.

861356493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5629804 (or 5629801 counting only the distinct ones).

The product of its digits is 466560, while the sum is 45.

The square root of 861356493 is about 29348.8754980493. The cubic root of 861356493 is about 951.4682717423.

The spelling of 861356493 in words is "eight hundred sixty-one million, three hundred fifty-six thousand, four hundred ninety-three".