637920043 has 2 divisors, whose sum is σ = 637920044. Its totient is φ = 637920042.

The previous prime is 637920013. The next prime is 637920061. The reversal of 637920043 is 340029736.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-637920043 is a prime.

It is a super-2 number, since 2×637920043² = 813883962522243698, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 637919990 and 637920008.

It is not a weakly prime, because it can be changed into another prime (637920013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318960021 + 318960022.

It is an arithmetic number, because the mean of its divisors is an integer number (318960022).

Almost surely, 2^637920043 is an apocalyptic number.

637920043 is a deficient number, since it is larger than the sum of its proper divisors (1).

637920043 is an equidigital number, since it uses as much as digits as its factorization.

637920043 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 34.

The square root of 637920043 is about 25257.0790670655. The cubic root of 637920043 is about 860.8392937717.

Adding to 637920043 its reverse (340029736), we get a palindrome (977949779).

The spelling of 637920043 in words is "six hundred thirty-seven million, nine hundred twenty thousand, forty-three".