351667681 has 4 divisors (see below), whose sum is σ = 354894100. Its totient is φ = 348441264.

The previous prime is 351667669. The next prime is 351667703. The reversal of 351667681 is 186766153.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 289510225 + 62157456 = 17015^2 + 7884^2 .

It is a cyclic number.

It is not a de Polignac number, because 351667681 - 2⁵ = 351667649 is a prime.

It is a super-2 number, since 2×351667681² = 247340315719835522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (351667651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1613046 + ... + 1613263.

It is an arithmetic number, because the mean of its divisors is an integer number (88723525).

Almost surely, 2^351667681 is an apocalyptic number.

It is an amenable number.

351667681 is a deficient number, since it is larger than the sum of its proper divisors (3226419).

351667681 is a wasteful number, since it uses less digits than its factorization.

351667681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3226418.

The product of its digits is 181440, while the sum is 43.

The square root of 351667681 is about 18752.8046169100. The cubic root of 351667681 is about 705.8473997879.

The spelling of 351667681 in words is "three hundred fifty-one million, six hundred sixty-seven thousand, six hundred eighty-one".