6420649 has 4 divisors (see below), whose sum is σ = 6459264. Its totient is φ = 6382036.

The previous prime is 6420599. The next prime is 6420683. The reversal of 6420649 is 9460246.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6420649 - 2¹³ = 6412457 is a prime.

It is a super-3 number, since 3×6420649³ (a number of 21 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6420649.

It is not an unprimeable number, because it can be changed into a prime (6423649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19057 + ... + 19390.

It is an arithmetic number, because the mean of its divisors is an integer number (1614816).

Almost surely, 2^6420649 is an apocalyptic number.

It is an amenable number.

6420649 is a deficient number, since it is larger than the sum of its proper divisors (38615).

6420649 is a wasteful number, since it uses less digits than its factorization.

6420649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38614.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 6420649 is about 2533.8999585619. The cubic root of 6420649 is about 185.8630143336.

The spelling of 6420649 in words is "six million, four hundred twenty thousand, six hundred forty-nine".