861240540 has 48 divisors (see below), whose sum is σ = 2438583840. Its totient is φ = 227082240.

The previous prime is 861240533. The next prime is 861240551. The reversal of 861240540 is 45042168.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 861240498 and 861240507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75301 + ... + 85980.

It is an arithmetic number, because the mean of its divisors is an integer number (50803830).

Almost surely, 2^861240540 is an apocalyptic number.

It is an amenable number.

861240540 is an abundant number, since it is smaller than the sum of its proper divisors (1577343300).

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

861240540 is a wasteful number, since it uses less digits than its factorization.

861240540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161382 (or 161380 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 861240540 is about 29346.9000066447. The cubic root of 861240540 is about 951.4255753085.

The spelling of 861240540 in words is "eight hundred sixty-one million, two hundred forty thousand, five hundred forty".