61688470538 has 4 divisors (see below), whose sum is σ = 92532705810. Its totient is φ = 30844235268.

The previous prime is 61688470517. The next prime is 61688470561. The reversal of 61688470538 is 83507488616.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 60773589529 + 914881009 = 246523^2 + 30247^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15422117633 + ... + 15422117636.

Almost surely, 2^61688470538 is an apocalyptic number.

61688470538 is a deficient number, since it is larger than the sum of its proper divisors (30844235272).

61688470538 is a wasteful number, since it uses less digits than its factorization.

61688470538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30844235271.

The product of its (nonzero) digits is 7741440, while the sum is 56.

The spelling of 61688470538 in words is "sixty-one billion, six hundred eighty-eight million, four hundred seventy thousand, five hundred thirty-eight".