645554380055 has 16 divisors (see below), whose sum is σ = 834949625664. Its totient is φ = 476320089600.

The previous prime is 645554379959. The next prime is 645554380063. The reversal of 645554380055 is 550083455546.

It is not a de Polignac number, because 645554380055 - 2²² = 645550185751 is a prime.

It is a super-3 number, since 3×645554380055³ (a number of 36 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645554379985 and 645554380012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4056659 + ... + 4212788.

It is an arithmetic number, because the mean of its divisors is an integer number (52184351604).

Almost surely, 2^645554380055 is an apocalyptic number.

645554380055 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

645554380055 is a deficient number, since it is larger than the sum of its proper divisors (189395245609).

645554380055 is a wasteful number, since it uses less digits than its factorization.

645554380055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8270666.

The product of its (nonzero) digits is 7200000, while the sum is 50.

The spelling of 645554380055 in words is "six hundred forty-five billion, five hundred fifty-four million, three hundred eighty thousand, fifty-five".