6891385140 has 36 divisors (see below), whose sum is σ = 20903868804. Its totient is φ = 1837702656.

The previous prime is 6891385133. The next prime is 6891385141. The reversal of 6891385140 is 415831986.

It can be written as a sum of positive squares in 2 ways, for example, as 1609293456 + 5282091684 = 40116^2 + 72678^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6891385141) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19142557 + ... + 19142916.

Almost surely, 2^6891385140 is an apocalyptic number.

6891385140 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6891385140 is an abundant number, since it is smaller than the sum of its proper divisors (14012483664).

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

6891385140 is a wasteful number, since it uses less digits than its factorization.

6891385140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38285488 (or 38285483 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 6891385140 is about 83014.3670698030. The cubic root of 6891385140 is about 1902.9856236270.

The spelling of 6891385140 in words is "six billion, eight hundred ninety-one million, three hundred eighty-five thousand, one hundred forty".