2181006388761 has 32 divisors (see below), whose sum is σ = 3009378493440. Its totient is φ = 1404403416000.

The previous prime is 2181006388663. The next prime is 2181006388763. The reversal of 2181006388761 is 1678836001812.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-2181006388761 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2181006388763) 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, 1876236 + ... + 2807538.

It is an arithmetic number, because the mean of its divisors is an integer number (94043077920).

Almost surely, 2^{2181006388761} is an apocalyptic number.

It is an amenable number.

2181006388761 is a deficient number, since it is larger than the sum of its proper divisors (828372104679).

2181006388761 is a wasteful number, since it uses less digits than its factorization.

2181006388761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 931597.

The product of its (nonzero) digits is 774144, while the sum is 51.

The spelling of 2181006388761 in words is "two trillion, one hundred eighty-one billion, six million, three hundred eighty-eight thousand, seven hundred sixty-one".