641439755 has 48 divisors (see below), whose sum is σ = 911941632. Its totient is φ = 431534400.

The previous prime is 641439751. The next prime is 641439769. The reversal of 641439755 is 557934146.

641439755 = T₃₀₆ + T₃₀₇ + ... + T₁₅₇₀.

It is not a de Polignac number, because 641439755 - 2² = 641439751 is a prime.

It is a super-2 number, since 2×641439755² = 822889918588920050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (641439751) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 430622 + ... + 432108.

It is an arithmetic number, because the mean of its divisors is an integer number (18998784).

Almost surely, 2^641439755 is an apocalyptic number.

641439755 is a deficient number, since it is larger than the sum of its proper divisors (270501877).

641439755 is a wasteful number, since it uses less digits than its factorization.

641439755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1568 (or 1557 counting only the distinct ones).

The product of its digits is 453600, while the sum is 44.

The square root of 641439755 is about 25326.6609524430. The cubic root of 641439755 is about 862.4196124757.

The spelling of 641439755 in words is "six hundred forty-one million, four hundred thirty-nine thousand, seven hundred fifty-five".