861921477152 has 54 divisors (see below), whose sum is σ = 1705460141637. Its totient is φ = 428799619584.

The previous prime is 861921477133. The next prime is 861921477167. The reversal of 861921477152 is 251774129168.

It is a happy number.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 813466901776 + 48454575376 = 901924^2 + 220124^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=656476.

It is a super-2 number, since 2×861921477152² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 861921477094 and 861921477103.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1769859053 + ... + 1769859539.

Almost surely, 2^861921477152 is an apocalyptic number.

It is an amenable number.

861921477152 is a deficient number, since it is larger than the sum of its proper divisors (843538664485).

861921477152 is an frugal number, since it uses more digits than its factorization.

861921477152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1658 (or 826 counting only the distinct ones).

The product of its digits is 1693440, while the sum is 53.

The spelling of 861921477152 in words is "eight hundred sixty-one billion, nine hundred twenty-one million, four hundred seventy-seven thousand, one hundred fifty-two".