2187720948125 has 10 divisors (see below), whose sum is σ = 2733776097558. Its totient is φ = 1750176758000.

The previous prime is 2187720948121. The next prime is 2187720948131. The reversal of 2187720948125 is 5218490277812.

It is a happy number.

It can be written as a sum of positive squares in 5 ways, for example, as 1485683080996 + 702037867129 = 1218886^2 + 837877^2 .

It is not a de Polignac number, because 2187720948125 - 2² = 2187720948121 is a prime.

It is a super-2 number, since 2×2187720948125² (a number of 25 digits) 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 (2187720948121) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1750176134 + ... + 1750177383.

Almost surely, 2^{2187720948125} is an apocalyptic number.

2187720948125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2187720948125 is a deficient number, since it is larger than the sum of its proper divisors (546055149433).

2187720948125 is an frugal number, since it uses more digits than its factorization.

2187720948125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3500353537 (or 3500353522 counting only the distinct ones).

The product of its (nonzero) digits is 4515840, while the sum is 56.

The spelling of 2187720948125 in words is "two trillion, one hundred eighty-seven billion, seven hundred twenty million, nine hundred forty-eight thousand, one hundred twenty-five".