64401940 has 12 divisors (see below), whose sum is σ = 135244116. Its totient is φ = 25760768.

The previous prime is 64401929. The next prime is 64401947. The reversal of 64401940 is 4910446.

64401940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 16016004 + 48385936 = 4002^2 + 6956^2 .

It is a junction number, because it is equal to n+sod(n) for n = 64401899 and 64401908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64401947) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1610029 + ... + 1610068.

It is an arithmetic number, because the mean of its divisors is an integer number (11270343).

Almost surely, 2^64401940 is an apocalyptic number.

It is an amenable number.

64401940 is an abundant number, since it is smaller than the sum of its proper divisors (70842176).

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

64401940 is a wasteful number, since it uses less digits than its factorization.

64401940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3220106 (or 3220104 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 64401940 is about 8025.0819310459. The cubic root of 64401940 is about 400.8356280986.

It can be divided in two parts, 64401 and 940, that added together give a triangular number (65341 = T₃₆₁).

The spelling of 64401940 in words is "sixty-four million, four hundred one thousand, nine hundred forty".