861252405 has 64 divisors (see below), whose sum is σ = 1517322240. Its totient is φ = 414602496.

The previous prime is 861252397. The next prime is 861252409. The reversal of 861252405 is 504252168.

It is not a de Polignac number, because 861252405 - 2³ = 861252397 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 (861252409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2055286 + ... + 2055704.

It is an arithmetic number, because the mean of its divisors is an integer number (23708160).

Almost surely, 2^861252405 is an apocalyptic number.

It is an amenable number.

861252405 is a deficient number, since it is larger than the sum of its proper divisors (656069835).

861252405 is a wasteful number, since it uses less digits than its factorization.

861252405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650.

The product of its (nonzero) digits is 19200, while the sum is 33.

The square root of 861252405 is about 29347.1021567718. The cubic root of 861252405 is about 951.4299444373.

The spelling of 861252405 in words is "eight hundred sixty-one million, two hundred fifty-two thousand, four hundred five".