6720457 has 4 divisors (see below), whose sum is σ = 7115796. Its totient is φ = 6325120.

The previous prime is 6720443. The next prime is 6720473. The reversal of 6720457 is 7540276.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4562496 + 2157961 = 2136^2 + 1469^2 .

It is a cyclic number.

It is not a de Polignac number, because 6720457 - 2¹⁵ = 6687689 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6720407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 197644 + ... + 197677.

It is an arithmetic number, because the mean of its divisors is an integer number (1778949).

Almost surely, 2^6720457 is an apocalyptic number.

It is an amenable number.

6720457 is a deficient number, since it is larger than the sum of its proper divisors (395339).

6720457 is a wasteful number, since it uses less digits than its factorization.

6720457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395338.

The product of its (nonzero) digits is 11760, while the sum is 31.

The square root of 6720457 is about 2592.3844236533. The cubic root of 6720457 is about 188.7120368660.

The spelling of 6720457 in words is "six million, seven hundred twenty thousand, four hundred fifty-seven".