2645551 has 2 divisors, whose sum is σ = 2645552. Its totient is φ = 2645550.

The previous prime is 2645549. The next prime is 2645561. The reversal of 2645551 is 1555462.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2645551 - 2¹ = 2645549 is a prime.

Together with 2645549, it forms a pair of twin primes.

It is equal to p₁₉₂₉₅₂ and since 2645551 and 192952 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2645521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1322775 + 1322776.

It is an arithmetic number, because the mean of its divisors is an integer number (1322776).

2^2645551 is an apocalyptic number.

2645551 is a deficient number, since it is larger than the sum of its proper divisors (1).

2645551 is an equidigital number, since it uses as much as digits as its factorization.

2645551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6000, while the sum is 28.

The square root of 2645551 is about 1626.5149860976. The cubic root of 2645551 is about 138.3052648653.

The spelling of 2645551 in words is "two million, six hundred forty-five thousand, five hundred fifty-one".