861820471 has 4 divisors (see below), whose sum is σ = 863314672. Its totient is φ = 860326272.

The previous prime is 861820469. The next prime is 861820481. The reversal of 861820471 is 174028168.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 861820471 - 2¹ = 861820469 is a prime.

It is a super-3 number, since 3×861820471³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 861820471.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861820441) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 746235 + ... + 747388.

It is an arithmetic number, because the mean of its divisors is an integer number (215828668).

Almost surely, 2^861820471 is an apocalyptic number.

861820471 is a deficient number, since it is larger than the sum of its proper divisors (1494201).

861820471 is a wasteful number, since it uses less digits than its factorization.

861820471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1494200.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 861820471 is about 29356.7789615959. The cubic root of 861820471 is about 951.6390802702.

The spelling of 861820471 in words is "eight hundred sixty-one million, eight hundred twenty thousand, four hundred seventy-one".