2145255421 has 2 divisors, whose sum is σ = 2145255422. Its totient is φ = 2145255420.

The previous prime is 2145255373. The next prime is 2145255443. The reversal of 2145255421 is 1245525412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1807100100 + 338155321 = 42510^2 + 18389^2 .

It is a cyclic number.

It is not a de Polignac number, because 2145255421 - 2¹⁹ = 2144731133 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2145255491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1072627710 + 1072627711.

It is an arithmetic number, because the mean of its divisors is an integer number (1072627711).

Almost surely, 2^2145255421 is an apocalyptic number.

It is an amenable number.

2145255421 is a deficient number, since it is larger than the sum of its proper divisors (1).

2145255421 is an equidigital number, since it uses as much as digits as its factorization.

2145255421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16000, while the sum is 31.

The square root of 2145255421 is about 46316.9021092732. The cubic root of 2145255421 is about 1289.7127780306.

The spelling of 2145255421 in words is "two billion, one hundred forty-five million, two hundred fifty-five thousand, four hundred twenty-one".