64861553403340 has 24 divisors (see below), whose sum is σ = 136278298855440. Its totient is φ = 25931471512128.

The previous prime is 64861553403337. The next prime is 64861553403341. The reversal of 64861553403340 is 4330435516846.

It is a happy number.

It is a super-2 number, since 2×64861553403340² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64861553403341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 821825130 + ... + 821904049.

It is an arithmetic number, because the mean of its divisors is an integer number (5678262452310).

Almost surely, 2^{64861553403340} is an apocalyptic number.

It is an amenable number.

64861553403340 is an abundant number, since it is smaller than the sum of its proper divisors (71416745452100).

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

64861553403340 is a wasteful number, since it uses less digits than its factorization.

64861553403340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1643731161 (or 1643731159 counting only the distinct ones).

The product of its (nonzero) digits is 12441600, while the sum is 52.

The spelling of 64861553403340 in words is "sixty-four trillion, eight hundred sixty-one billion, five hundred fifty-three million, four hundred three thousand, three hundred forty".