6810400657 has 4 divisors (see below), whose sum is σ = 6912048496. Its totient is φ = 6708752820.

The previous prime is 6810400631. The next prime is 6810400669. The reversal of 6810400657 is 7560040186.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7560040186 = 2 ⋅3780020093.

It is a cyclic number.

It is not a de Polignac number, because 6810400657 - 2⁷ = 6810400529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6810400057) 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, 50823819 + ... + 50823952.

It is an arithmetic number, because the mean of its divisors is an integer number (1728012124).

Almost surely, 2^6810400657 is an apocalyptic number.

6810400657 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

It is an amenable number.

6810400657 is a deficient number, since it is larger than the sum of its proper divisors (101647839).

6810400657 is a wasteful number, since it uses less digits than its factorization.

6810400657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101647838.

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 6810400657 is about 82525.1516629930. The cubic root of 6810400657 is about 1895.5018854769.

The spelling of 6810400657 in words is "six billion, eight hundred ten million, four hundred thousand, six hundred fifty-seven".