641472820 has 24 divisors (see below), whose sum is σ = 1349476128. Its totient is φ = 256135200.

The previous prime is 641472817. The next prime is 641472847. The reversal of 641472820 is 28274146.

It is a happy number.

It is a super-2 number, since 2×641472820² = 822974757597504800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16666 + ... + 39505.

It is an arithmetic number, because the mean of its divisors is an integer number (56228172).

Almost surely, 2^641472820 is an apocalyptic number.

It is an amenable number.

641472820 is an abundant number, since it is smaller than the sum of its proper divisors (708003308).

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

641472820 is a wasteful number, since it uses less digits than its factorization.

641472820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56751 (or 56749 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 641472820 is about 25327.3137146441. The cubic root of 641472820 is about 862.4344309182.

The spelling of 641472820 in words is "six hundred forty-one million, four hundred seventy-two thousand, eight hundred twenty".