681486778 has 16 divisors (see below), whose sum is σ = 1168873920. Its totient is φ = 291913056.

The previous prime is 681486763. The next prime is 681486779. The reversal of 681486778 is 877684186.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (681486779) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17478 + ... + 40846.

It is an arithmetic number, because the mean of its divisors is an integer number (73054620).

Almost surely, 2^681486778 is an apocalyptic number.

681486778 is a deficient number, since it is larger than the sum of its proper divisors (487387142).

681486778 is a wasteful number, since it uses less digits than its factorization.

681486778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25461.

The product of its digits is 3612672, while the sum is 55.

The square root of 681486778 is about 26105.3017220640. The cubic root of 681486778 is about 880.0063610077.

The spelling of 681486778 in words is "six hundred eighty-one million, four hundred eighty-six thousand, seven hundred seventy-eight".