5261390691 has 8 divisors (see below), whose sum is σ = 7320195840. Its totient is φ = 3355089672.

The previous prime is 5261390663. The next prime is 5261390731. The reversal of 5261390691 is 1960931625.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 5261390691 - 2⁹ = 5261390179 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (5261390621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38125951 + ... + 38126088.

It is an arithmetic number, because the mean of its divisors is an integer number (915024480).

Almost surely, 2^5261390691 is an apocalyptic number.

5261390691 is a deficient number, since it is larger than the sum of its proper divisors (2058805149).

5261390691 is a wasteful number, since it uses less digits than its factorization.

5261390691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76252065.

The product of its (nonzero) digits is 87480, while the sum is 42.

The square root of 5261390691 is about 72535.4443772146. Note that the first 3 decimals coincide. The cubic root of 5261390691 is about 1739.2693778249.

The spelling of 5261390691 in words is "five billion, two hundred sixty-one million, three hundred ninety thousand, six hundred ninety-one".