861648550 has 24 divisors (see below), whose sum is σ = 1831619376. Its totient is φ = 295422240.

The previous prime is 861648443. The next prime is 861648581. The reversal of 861648550 is 55846168.

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 861648497 and 861648506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1230577 + ... + 1231276.

It is an arithmetic number, because the mean of its divisors is an integer number (76317474).

Almost surely, 2^861648550 is an apocalyptic number.

861648550 is an abundant number, since it is smaller than the sum of its proper divisors (969970826).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861648550 is a wasteful number, since it uses less digits than its factorization.

861648550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2461872 (or 2461867 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 43.

The square root of 861648550 is about 29353.8506843651. The cubic root of 861648550 is about 951.5757965477.

The spelling of 861648550 in words is "eight hundred sixty-one million, six hundred forty-eight thousand, five hundred fifty".