891391140 has 36 divisors (see below), whose sum is σ = 2703887004. Its totient is φ = 237704256.

The previous prime is 891391133. The next prime is 891391147. The reversal of 891391140 is 41193198.

It is an interprime number because it is at equal distance from previous prime (891391133) and next prime (891391147).

It can be written as a sum of positive squares in 2 ways, for example, as 317980224 + 573410916 = 17832^2 + 23946^2 .

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 (36).

It is a junction number, because it is equal to n+sod(n) for n = 891391095 and 891391104.

It is not an unprimeable number, because it can be changed into a prime (891391147) 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, 2475907 + ... + 2476266.

Almost surely, 2^891391140 is an apocalyptic number.

It is an amenable number.

891391140 is an abundant number, since it is smaller than the sum of its proper divisors (1812495864).

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

891391140 is a wasteful number, since it uses less digits than its factorization.

891391140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4952188 (or 4952183 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 891391140 is about 29856.1742358260. The cubic root of 891391140 is about 962.4010859166.

The spelling of 891391140 in words is "eight hundred ninety-one million, three hundred ninety-one thousand, one hundred forty".