61551444142640 has 80 divisors (see below), whose sum is σ = 144449242299648. Its totient is φ = 24389687701248.

The previous prime is 61551444142609. The next prime is 61551444142673. The reversal of 61551444142640 is 4624144415516.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 312880949 + ... + 313077611.

Almost surely, 2^{61551444142640} is an apocalyptic number.

It is an amenable number.

61551444142640 is an abundant number, since it is smaller than the sum of its proper divisors (82897798157008).

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

61551444142640 is a wasteful number, since it uses less digits than its factorization.

61551444142640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233346 (or 233340 counting only the distinct ones).

The product of its (nonzero) digits is 1843200, while the sum is 47.

The spelling of 61551444142640 in words is "sixty-one trillion, five hundred fifty-one billion, four hundred forty-four million, one hundred forty-two thousand, six hundred forty".