64161261556 has 24 divisors (see below), whose sum is σ = 128833782336. Its totient is φ = 27388128000.

The previous prime is 64161261553. The next prime is 64161261559. The reversal of 64161261556 is 65516216146.

It is an interprime number because it is at equal distance from previous prime (64161261553) and next prime (64161261559).

It is a super-2 number, since 2×64161261556² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64161261553) 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, 4557661 + ... + 4571716.

It is an arithmetic number, because the mean of its divisors is an integer number (5368074264).

Almost surely, 2^64161261556 is an apocalyptic number.

It is an amenable number.

64161261556 is an abundant number, since it is smaller than the sum of its proper divisors (64672520780).

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

64161261556 is a wasteful number, since it uses less digits than its factorization.

64161261556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9129639 (or 9129637 counting only the distinct ones).

The product of its digits is 259200, while the sum is 43.

The spelling of 64161261556 in words is "sixty-four billion, one hundred sixty-one million, two hundred sixty-one thousand, five hundred fifty-six".