869139640 has 32 divisors (see below), whose sum is σ = 2040590880. Its totient is φ = 332540032.

The previous prime is 869139589. The next prime is 869139641. The reversal of 869139640 is 46931968.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (869139641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 471439 + ... + 473278.

It is an arithmetic number, because the mean of its divisors is an integer number (63768465).

Almost surely, 2^869139640 is an apocalyptic number.

It is an amenable number.

869139640 is an abundant number, since it is smaller than the sum of its proper divisors (1171451240).

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

869139640 is a wasteful number, since it uses less digits than its factorization.

869139640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 944751 (or 944747 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 46.

The square root of 869139640 is about 29481.1743321056. The cubic root of 869139640 is about 954.3254796728.

The spelling of 869139640 in words is "eight hundred sixty-nine million, one hundred thirty-nine thousand, six hundred forty".