9991426237 has 8 divisors (see below), whose sum is σ = 10798293240. Its totient is φ = 9190030080.

The previous prime is 9991426183. The next prime is 9991426301. The reversal of 9991426237 is 7326241999.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 436559236 + 9554867001 = 20894^2 + 97749^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 9991426237 - 2²³ = 9983037629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9991426037) 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, 1363912 + ... + 1371217.

It is an arithmetic number, because the mean of its divisors is an integer number (1349786655).

Almost surely, 2^9991426237 is an apocalyptic number.

It is an amenable number.

9991426237 is a deficient number, since it is larger than the sum of its proper divisors (806867003).

9991426237 is a wasteful number, since it uses less digits than its factorization.

9991426237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2735423.

The product of its digits is 1469664, while the sum is 52.

The square root of 9991426237 is about 99957.1219923823. The cubic root of 9991426237 is about 2153.8187935656.

The spelling of 9991426237 in words is "nine billion, nine hundred ninety-one million, four hundred twenty-six thousand, two hundred thirty-seven".