891405601 has 4 divisors (see below), whose sum is σ = 892874752. Its totient is φ = 889936452.

The previous prime is 891405563. The next prime is 891405607. The reversal of 891405601 is 106504198.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 106504198 = 2 ⋅53252099.

It is a cyclic number.

It is not a de Polignac number, because 891405601 - 2¹⁷ = 891274529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (891405607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 733665 + ... + 734878.

It is an arithmetic number, because the mean of its divisors is an integer number (223218688).

Almost surely, 2^891405601 is an apocalyptic number.

It is an amenable number.

891405601 is a deficient number, since it is larger than the sum of its proper divisors (1469151).

891405601 is a wasteful number, since it uses less digits than its factorization.

891405601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1469150.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 891405601 is about 29856.4164125569. The cubic root of 891405601 is about 962.4062902189.

Adding to 891405601 its reverse (106504198), we get a palindrome (997909799).

The spelling of 891405601 in words is "eight hundred ninety-one million, four hundred five thousand, six hundred one".