537891691 has 4 divisors (see below), whose sum is σ = 566201800. Its totient is φ = 509581584.

The previous prime is 537891659. The next prime is 537891701. The reversal of 537891691 is 196198735.

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

It is a cyclic number.

It is not a de Polignac number, because 537891691 - 2⁵ = 537891659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (537891631) 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, 14155026 + ... + 14155063.

It is an arithmetic number, because the mean of its divisors is an integer number (141550450).

Almost surely, 2^537891691 is an apocalyptic number.

537891691 is a deficient number, since it is larger than the sum of its proper divisors (28310109).

537891691 is a wasteful number, since it uses less digits than its factorization.

537891691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28310108.

The product of its digits is 408240, while the sum is 49.

The square root of 537891691 is about 23192.4921256858. The cubic root of 537891691 is about 813.2641192146.

The spelling of 537891691 in words is "five hundred thirty-seven million, eight hundred ninety-one thousand, six hundred ninety-one".