681401945 has 8 divisors (see below), whose sum is σ = 934494144. Its totient is φ = 467247024.

The previous prime is 681401899. The next prime is 681401947. The reversal of 681401945 is 549104186.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 681401945 - 2⁶ = 681401881 is a prime.

It is a super-2 number, since 2×681401945² = 928617221299566050, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 681401899 and 681401908.

It is not an unprimeable number, because it can be changed into a prime (681401947) 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, 9734279 + ... + 9734348.

It is an arithmetic number, because the mean of its divisors is an integer number (116811768).

Almost surely, 2^681401945 is an apocalyptic number.

It is an amenable number.

681401945 is a deficient number, since it is larger than the sum of its proper divisors (253092199).

681401945 is a wasteful number, since it uses less digits than its factorization.

681401945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19468639.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 681401945 is about 26103.6768482909. The cubic root of 681401945 is about 879.9698444384.

The spelling of 681401945 in words is "six hundred eighty-one million, four hundred one thousand, nine hundred forty-five".