649299021 has 8 divisors (see below), whose sum is σ = 989408064. Its totient is φ = 371028000.

The previous prime is 649298983. The next prime is 649299041. The reversal of 649299021 is 120992946.

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

It is not a de Polignac number, because 649299021 - 2¹⁴ = 649282637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649299041) 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, 15459480 + ... + 15459521.

It is an arithmetic number, because the mean of its divisors is an integer number (123676008).

Almost surely, 2^649299021 is an apocalyptic number.

It is an amenable number.

649299021 is a deficient number, since it is larger than the sum of its proper divisors (340109043).

649299021 is a wasteful number, since it uses less digits than its factorization.

649299021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30919011.

The product of its (nonzero) digits is 69984, while the sum is 42.

The square root of 649299021 is about 25481.3465303543. The cubic root of 649299021 is about 865.9276008115.

The spelling of 649299021 in words is "six hundred forty-nine million, two hundred ninety-nine thousand, twenty-one".