637421243 has 4 divisors (see below), whose sum is σ = 639689928. Its totient is φ = 635152560.

The previous prime is 637421231. The next prime is 637421249. The reversal of 637421243 is 342124736.

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 637421243 - 2⁴ = 637421227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (637421249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1133921 + ... + 1134482.

It is an arithmetic number, because the mean of its divisors is an integer number (159922482).

Almost surely, 2^637421243 is an apocalyptic number.

637421243 is a deficient number, since it is larger than the sum of its proper divisors (2268685).

637421243 is a wasteful number, since it uses less digits than its factorization.

637421243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2268684.

The product of its digits is 24192, while the sum is 32.

The square root of 637421243 is about 25247.2026767323. The cubic root of 637421243 is about 860.6148672113.

Adding to 637421243 its reverse (342124736), we get a palindrome (979545979).

The spelling of 637421243 in words is "six hundred thirty-seven million, four hundred twenty-one thousand, two hundred forty-three".