644100694167 has 16 divisors (see below), whose sum is σ = 981876177152. Its totient is φ = 367911512640.

The previous prime is 644100694117. The next prime is 644100694217. The reversal of 644100694167 is 761496001446.

It is an interprime number because it is at equal distance from previous prime (644100694117) and next prime (644100694217).

It is not a de Polignac number, because 644100694167 - 2⁸ = 644100693911 is a prime.

It is a super-2 number, since 2×644100694167² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644100694117) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6030253 + ... + 6136134.

It is an arithmetic number, because the mean of its divisors is an integer number (61367261072).

Almost surely, 2^644100694167 is an apocalyptic number.

644100694167 is a deficient number, since it is larger than the sum of its proper divisors (337775482985).

644100694167 is a wasteful number, since it uses less digits than its factorization.

644100694167 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12168918.

The product of its (nonzero) digits is 870912, while the sum is 48.

The spelling of 644100694167 in words is "six hundred forty-four billion, one hundred million, six hundred ninety-four thousand, one hundred sixty-seven".