6656437 has 2 divisors, whose sum is σ = 6656438. Its totient is φ = 6656436.

The previous prime is 6656393. The next prime is 6656449. The reversal of 6656437 is 7346566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4468996 + 2187441 = 2114^2 + 1479^2 .

It is a cyclic number.

It is not a de Polignac number, because 6656437 - 2¹⁹ = 6132149 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6656396 and 6656405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6656497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3328218 + 3328219.

It is an arithmetic number, because the mean of its divisors is an integer number (3328219).

Almost surely, 2^6656437 is an apocalyptic number.

It is an amenable number.

6656437 is a deficient number, since it is larger than the sum of its proper divisors (1).

6656437 is an equidigital number, since it uses as much as digits as its factorization.

6656437 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 37.

The square root of 6656437 is about 2580.0071705327. The cubic root of 6656437 is about 188.1108916474.

Subtracting from 6656437 its sum of digits (37), we obtain a square (6656400 = 2580²).

The spelling of 6656437 in words is "six million, six hundred fifty-six thousand, four hundred thirty-seven".