672742803681 has 27 divisors (see below), whose sum is σ = 1052288779347. Its totient is φ = 413975886480.

The previous prime is 672742803673. The next prime is 672742803697. The reversal of 672742803681 is 186308247276.

The square root of 672742803681 is 820209.

It is a perfect power (a square), and thus also a powerful number.

672742803681 is a `hidden beast` number, since 6 + 7 + 274 + 2 + 8 + 0 + 368 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 99518166225 + 573224637456 = 315465^2 + 757116^2 .

It is not a de Polignac number, because 672742803681 - 2³ = 672742803673 is a prime.

It is a super-2 number, since 2×672742803681² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (672742803641) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 31977636 + ... + 31998666.

Almost surely, 2^672742803681 is an apocalyptic number.

672742803681 is the 820209-th square number.

672742803681 is the 410105-th centered octagonal number.

It is an amenable number.

672742803681 is a deficient number, since it is larger than the sum of its proper divisors (379545975666).

672742803681 is an frugal number, since it uses more digits than its factorization.

672742803681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42094 (or 21047 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 54.

The spelling of 672742803681 in words is "six hundred seventy-two billion, seven hundred forty-two million, eight hundred three thousand, six hundred eighty-one".