681406049 has 4 divisors (see below), whose sum is σ = 684830400. Its totient is φ = 677981700.

The previous prime is 681406039. The next prime is 681406057. The reversal of 681406049 is 940604186.

681406049 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 681406049 - 2⁸ = 681405793 is a prime.

It is a super-2 number, since 2×681406049² = 928628407227580802, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681406039) 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, 1711877 + ... + 1712274.

It is an arithmetic number, because the mean of its divisors is an integer number (171207600).

Almost surely, 2^681406049 is an apocalyptic number.

It is an amenable number.

681406049 is a deficient number, since it is larger than the sum of its proper divisors (3424351).

681406049 is a wasteful number, since it uses less digits than its factorization.

681406049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3424350.

The product of its (nonzero) digits is 41472, while the sum is 38.

The square root of 681406049 is about 26103.7554577881. The cubic root of 681406049 is about 879.9716110849.

The spelling of 681406049 in words is "six hundred eighty-one million, four hundred six thousand, forty-nine".