535661891 has 4 divisors (see below), whose sum is σ = 567171432. Its totient is φ = 504152352.

The previous prime is 535661873. The next prime is 535661899. The reversal of 535661891 is 198166535.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-535661891 is a prime.

It is a super-2 number, since 2×535661891² = 573867322939391762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (535661899) 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, 15754745 + ... + 15754778.

It is an arithmetic number, because the mean of its divisors is an integer number (141792858).

Almost surely, 2^535661891 is an apocalyptic number.

535661891 is a deficient number, since it is larger than the sum of its proper divisors (31509541).

535661891 is a wasteful number, since it uses less digits than its factorization.

535661891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31509540.

The product of its digits is 194400, while the sum is 44.

The square root of 535661891 is about 23144.3706114467. The cubic root of 535661891 is about 812.1387824255.

The spelling of 535661891 in words is "five hundred thirty-five million, six hundred sixty-one thousand, eight hundred ninety-one".