2137873921 has 2 divisors, whose sum is σ = 2137873922. Its totient is φ = 2137873920.

The previous prime is 2137873919. The next prime is 2137873951. The reversal of 2137873921 is 1293787312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1961515521 + 176358400 = 44289^2 + 13280^2 .

It is a cyclic number.

It is not a de Polignac number, because 2137873921 - 2¹ = 2137873919 is a prime.

Together with 2137873919, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2137873951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1068936960 + 1068936961.

It is an arithmetic number, because the mean of its divisors is an integer number (1068936961).

Almost surely, 2^2137873921 is an apocalyptic number.

It is an amenable number.

2137873921 is a deficient number, since it is larger than the sum of its proper divisors (1).

2137873921 is an equidigital number, since it uses as much as digits as its factorization.

2137873921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 43.

The square root of 2137873921 is about 46237.1487118313. The cubic root of 2137873921 is about 1288.2318425243.

The spelling of 2137873921 in words is "two billion, one hundred thirty-seven million, eight hundred seventy-three thousand, nine hundred twenty-one".