2187221694061 has 2 divisors, whose sum is σ = 2187221694062. Its totient is φ = 2187221694060.

The previous prime is 2187221694059. The next prime is 2187221694113. The reversal of 2187221694061 is 1604961227812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2066639131561 + 120582562500 = 1437581^2 + 347250^2 .

It is a cyclic number.

It is not a de Polignac number, because 2187221694061 - 2¹ = 2187221694059 is a prime.

Together with 2187221694059, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 2187221693996 and 2187221694014.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2187221694661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1093610847030 + 1093610847031.

It is an arithmetic number, because the mean of its divisors is an integer number (1093610847031).

Almost surely, 2^{2187221694061} is an apocalyptic number.

It is an amenable number.

2187221694061 is a deficient number, since it is larger than the sum of its proper divisors (1).

2187221694061 is an equidigital number, since it uses as much as digits as its factorization.

2187221694061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 580608, while the sum is 49.

The spelling of 2187221694061 in words is "two trillion, one hundred eighty-seven billion, two hundred twenty-one million, six hundred ninety-four thousand, sixty-one".