649210681 has 8 divisors (see below), whose sum is σ = 752119424. Its totient is φ = 548843040.

The previous prime is 649210657. The next prime is 649210691. The reversal of 649210681 is 186012946.

It is a happy number.

649210681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 649210681 - 2⁷ = 649210553 is a prime.

It is a super-2 number, since 2×649210681² = 842949016648967522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 649210681.

It is not an unprimeable number, because it can be changed into a prime (649210631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 634725 + ... + 635746.

It is an arithmetic number, because the mean of its divisors is an integer number (94014928).

Almost surely, 2^649210681 is an apocalyptic number.

It is an amenable number.

649210681 is a deficient number, since it is larger than the sum of its proper divisors (102908743).

649210681 is a wasteful number, since it uses less digits than its factorization.

649210681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1270551.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 649210681 is about 25479.6130465123. The cubic root of 649210681 is about 865.8883279386. Note that the first 3 decimals are identical.

The spelling of 649210681 in words is "six hundred forty-nine million, two hundred ten thousand, six hundred eighty-one".