61280137344 has 128 divisors (see below), whose sum is σ = 168970752000. Its totient is φ = 19656668160.

The previous prime is 61280137319. The next prime is 61280137349. The reversal of 61280137344 is 44373108216.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (61280137349) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2116437 + ... + 2145195.

It is an arithmetic number, because the mean of its divisors is an integer number (1320084000).

Almost surely, 2^61280137344 is an apocalyptic number.

61280137344 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61280137344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84485376000).

61280137344 is an abundant number, since it is smaller than the sum of its proper divisors (107690614656).

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

61280137344 is a wasteful number, since it uses less digits than its factorization.

61280137344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28986 (or 28974 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 39.

The spelling of 61280137344 in words is "sixty-one billion, two hundred eighty million, one hundred thirty-seven thousand, three hundred forty-four".