649549261 has 2 divisors, whose sum is σ = 649549262. Its totient is φ = 649549260.

The previous prime is 649549177. The next prime is 649549283. The reversal of 649549261 is 162945946.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 449864100 + 199685161 = 21210^2 + 14131^2 .

It is a cyclic number.

It is not a de Polignac number, because 649549261 - 2¹³ = 649541069 is a prime.

It is a super-2 number, since 2×649549261² = 843828484931292242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (649544261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324774630 + 324774631.

It is an arithmetic number, because the mean of its divisors is an integer number (324774631).

Almost surely, 2^649549261 is an apocalyptic number.

It is an amenable number.

649549261 is a deficient number, since it is larger than the sum of its proper divisors (1).

649549261 is an equidigital number, since it uses as much as digits as its factorization.

649549261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 466560, while the sum is 46.

The square root of 649549261 is about 25486.2563159049. The cubic root of 649549261 is about 866.0388294259.

The spelling of 649549261 in words is "six hundred forty-nine million, five hundred forty-nine thousand, two hundred sixty-one".