16001649 has 24 divisors (see below), whose sum is σ = 24571560. Its totient is φ = 10015488.

The previous prime is 16001599. The next prime is 16001659. The reversal of 16001649 is 94610061.

16001649 is a `hidden beast` number, since 1 + 600 + 16 + 49 = 666.

16001649 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 4223025 + 11778624 = 2055^2 + 3432^2 .

It is not a de Polignac number, because 16001649 - 2⁸ = 16001393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16001659) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8829 + ... + 10485.

It is an arithmetic number, because the mean of its divisors is an integer number (1023815).

Almost surely, 2^16001649 is an apocalyptic number.

It is an amenable number.

16001649 is a deficient number, since it is larger than the sum of its proper divisors (8569911).

16001649 is a wasteful number, since it uses less digits than its factorization.

16001649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1729 (or 1726 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 16001649 is about 4000.2061196893. The cubic root of 16001649 is about 251.9928663891.

It can be divided in two parts, 1600 and 1649, that added together give a square (3249 = 57²).

The spelling of 16001649 in words is "sixteen million, one thousand, six hundred forty-nine".