681749451 has 12 divisors (see below), whose sum is σ = 986247600. Its totient is φ = 453808080.

The previous prime is 681749449. The next prime is 681749459. The reversal of 681749451 is 154947186.

681749451 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 681749451 - 2¹ = 681749449 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 681749397 and 681749406.

It is not an unprimeable number, because it can be changed into a prime (681749459) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 51351 + ... + 63248.

It is an arithmetic number, because the mean of its divisors is an integer number (82187300).

Almost surely, 2^681749451 is an apocalyptic number.

681749451 is a deficient number, since it is larger than the sum of its proper divisors (304498149).

681749451 is a wasteful number, since it uses less digits than its factorization.

681749451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115266 (or 115263 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 681749451 is about 26110.3322652164. The cubic root of 681749451 is about 880.1194100186.

The spelling of 681749451 in words is "six hundred eighty-one million, seven hundred forty-nine thousand, four hundred fifty-one".