644149152 has 48 divisors (see below), whose sum is σ = 1878770880. Its totient is φ = 214716096.

The previous prime is 644149123. The next prime is 644149183. The reversal of 644149152 is 251941446.

644149152 is a `hidden beast` number, since 644 + 1 + 4 + 9 + 1 + 5 + 2 = 666.

644149152 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 371908 + ... + 373635.

It is an arithmetic number, because the mean of its divisors is an integer number (39141060).

Almost surely, 2^644149152 is an apocalyptic number.

It is an amenable number.

644149152 is an abundant number, since it is smaller than the sum of its proper divisors (1234621728).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644149152 is a wasteful number, since it uses less digits than its factorization.

644149152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 745562 (or 745548 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 644149152 is about 25380.0936168486. The cubic root of 644149152 is about 863.6321736763.

The spelling of 644149152 in words is "six hundred forty-four million, one hundred forty-nine thousand, one hundred fifty-two".