2661543937 has 4 divisors (see below), whose sum is σ = 2866278100. Its totient is φ = 2456809776.

The previous prime is 2661543889. The next prime is 2661543943. The reversal of 2661543937 is 7393451662.

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 1787513841 + 874030096 = 42279^2 + 29564^2 .

It is a cyclic number.

It is not a de Polignac number, because 2661543937 - 2⁷ = 2661543809 is a prime.

It is a super-2 number, since 2×2661543937² = 14167632257162919938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2661543947) 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, 102367062 + ... + 102367087.

It is an arithmetic number, because the mean of its divisors is an integer number (716569525).

Almost surely, 2^2661543937 is an apocalyptic number.

It is an amenable number.

2661543937 is a deficient number, since it is larger than the sum of its proper divisors (204734163).

2661543937 is a wasteful number, since it uses less digits than its factorization.

2661543937 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204734162.

The product of its digits is 816480, while the sum is 46.

The square root of 2661543937 is about 51590.1534888199. The cubic root of 2661543937 is about 1385.8340038938.

The spelling of 2661543937 in words is "two billion, six hundred sixty-one million, five hundred forty-three thousand, nine hundred thirty-seven".