861887901 has 48 divisors (see below), whose sum is σ = 1402320384. Its totient is φ = 468601056.

The previous prime is 861887893. The next prime is 861887911. The reversal of 861887901 is 109788168.

It is not a de Polignac number, because 861887901 - 2³ = 861887893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861887911) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 766926 + ... + 768048.

It is an arithmetic number, because the mean of its divisors is an integer number (29215008).

Almost surely, 2^861887901 is an apocalyptic number.

It is an amenable number.

861887901 is a deficient number, since it is larger than the sum of its proper divisors (540432483).

861887901 is a wasteful number, since it uses less digits than its factorization.

861887901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1390 (or 1383 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 48.

The square root of 861887901 is about 29357.9273961906. The cubic root of 861887901 is about 951.6638987995.

The spelling of 861887901 in words is "eight hundred sixty-one million, eight hundred eighty-seven thousand, nine hundred one".