394666759867680 has 72 divisors (see below), whose sum is σ = 1346800318053372. Its totient is φ = 105244469297664.

The previous prime is 394666759867651. The next prime is 394666759867711. The reversal of 394666759867680 is 86768957666493.

It can be written as a sum of positive squares in 2 ways, for example, as 385758039244176 + 8908720623504 = 19640724^2 + 2984748^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×394666759867680² (a number of 30 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (90).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 137037067959 + ... + 137037070838.

Almost surely, 2^{394666759867680} is an apocalyptic number.

394666759867680 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

394666759867680 is an abundant number, since it is smaller than the sum of its proper divisors (952133558185692).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

394666759867680 is a wasteful number, since it uses less digits than its factorization.

394666759867680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274074138818 (or 274074138807 counting only the distinct ones).

The product of its (nonzero) digits is 118513704960, while the sum is 90.

The spelling of 394666759867680 in words is "three hundred ninety-four trillion, six hundred sixty-six billion, seven hundred fifty-nine million, eight hundred sixty-seven thousand, six hundred eighty".