2571649 has 2 divisors, whose sum is σ = 2571650. Its totient is φ = 2571648.

The previous prime is 2571619. The next prime is 2571671. The reversal of 2571649 is 9461752.

2571649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1703025 + 868624 = 1305^2 + 932^2 .

It is a cyclic number.

It is not a de Polignac number, because 2571649 - 2¹⁷ = 2440577 is a prime.

It is a super-2 number, since 2×2571649² = 13226757158402, which contains 22 as substring.

It is equal to p₁₈₇₉₂₇ and since 2571649 and 187927 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (2571619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1285824 + 1285825.

It is an arithmetic number, because the mean of its divisors is an integer number (1285825).

2^2571649 is an apocalyptic number.

It is an amenable number.

2571649 is a deficient number, since it is larger than the sum of its proper divisors (1).

2571649 is an equidigital number, since it uses as much as digits as its factorization.

2571649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15120, while the sum is 34.

The square root of 2571649 is about 1603.6361806844. The cubic root of 2571649 is about 137.0052566935.

It can be divided in two parts, 257164 and 9, that multiplied together give a triangular number (2314476 = T₂₁₅₁).

The spelling of 2571649 in words is "two million, five hundred seventy-one thousand, six hundred forty-nine".