7921237 has 2 divisors, whose sum is σ = 7921238. Its totient is φ = 7921236.

The previous prime is 7921229. The next prime is 7921247. The reversal of 7921237 is 7321297.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7623121 + 298116 = 2761^2 + 546^2 .

It is a cyclic number.

It is not a de Polignac number, because 7921237 - 2³ = 7921229 is a prime.

It is a super-2 number, since 2×7921237² = 125491991220338, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7921199 and 7921208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7921247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3960618 + 3960619.

It is an arithmetic number, because the mean of its divisors is an integer number (3960619).

Almost surely, 2^7921237 is an apocalyptic number.

It is an amenable number.

7921237 is a deficient number, since it is larger than the sum of its proper divisors (1).

7921237 is an equidigital number, since it uses as much as digits as its factorization.

7921237 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5292, while the sum is 31.

The square root of 7921237 is about 2814.4692217184. The cubic root of 7921237 is about 199.3414757757.

It can be divided in two parts, 79 and 21237, that added together give a square (21316 = 146²).

The spelling of 7921237 in words is "seven million, nine hundred twenty-one thousand, two hundred thirty-seven".