3672643981 has 4 divisors (see below), whose sum is σ = 3672892764. Its totient is φ = 3672395200.

The previous prime is 3672643963. The next prime is 3672643987. The reversal of 3672643981 is 1893462763.

3672643981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 2818017225 + 854626756 = 53085^2 + 29234^2 .

It is a cyclic number.

It is not a de Polignac number, because 3672643981 - 2²¹ = 3670546829 is a prime.

It is a super-2 number, since 2×3672643981² = 26976627622351056722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3672643987) 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, 100750 + ... + 132271.

It is an arithmetic number, because the mean of its divisors is an integer number (918223191).

Almost surely, 2^3672643981 is an apocalyptic number.

It is an amenable number.

3672643981 is a deficient number, since it is larger than the sum of its proper divisors (248783).

3672643981 is a wasteful number, since it uses less digits than its factorization.

3672643981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248782.

The product of its digits is 1306368, while the sum is 49.

The square root of 3672643981 is about 60602.3430322624. The cubic root of 3672643981 is about 1542.8591373852.

The spelling of 3672643981 in words is "three billion, six hundred seventy-two million, six hundred forty-three thousand, nine hundred eighty-one".