649251 has 6 divisors (see below), whose sum is σ = 937820. Its totient is φ = 432828.

The previous prime is 649217. The next prime is 649261. The reversal of 649251 is 152946.

649251 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 649251 - 2⁷ = 649123 is a prime.

It is a super-2 number, since 2×649251² = 843053722002, which contains 22 as substring.

It is a Duffinian number.

649251 is strictly pandigital in base 7.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 649251.

It is not an unprimeable number, because it can be changed into a prime (649261) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36061 + ... + 36078.

2⁶⁴⁹²⁵¹ is an apocalyptic number.

649251 is a deficient number, since it is larger than the sum of its proper divisors (288569).

649251 is a wasteful number, since it uses less digits than its factorization.

649251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72145 (or 72142 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 649251 is about 805.7611308570. The cubic root of 649251 is about 86.5906252797.

It can be divided in two parts, 649 and 251, that added together give a square (900 = 30²).

The spelling of 649251 in words is "six hundred forty-nine thousand, two hundred fifty-one".