2661051987 has 32 divisors (see below), whose sum is σ = 4405605120. Its totient is φ = 1573416000.

The previous prime is 2661051979. The next prime is 2661052013. The reversal of 2661051987 is 7891501662.

2661051987 is a `hidden beast` number, since 26 + 610 + 5 + 1 + 9 + 8 + 7 = 666.

It is not a de Polignac number, because 2661051987 - 2³ = 2661051979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2661051917) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 97089 + ... + 121442.

It is an arithmetic number, because the mean of its divisors is an integer number (137675160).

Almost surely, 2^2661051987 is an apocalyptic number.

2661051987 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

2661051987 is a deficient number, since it is larger than the sum of its proper divisors (1744553133).

2661051987 is a wasteful number, since it uses less digits than its factorization.

2661051987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218592 (or 218586 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The square root of 2661051987 is about 51585.3854012936. The cubic root of 2661051987 is about 1385.7486144778.

The spelling of 2661051987 in words is "two billion, six hundred sixty-one million, fifty-one thousand, nine hundred eighty-seven".