61686890934638 has 16 divisors (see below), whose sum is σ = 98196471188640. Its totient is φ = 28962999568896.

The previous prime is 61686890934637. The next prime is 61686890934659. The reversal of 61686890934638 is 83643909868616.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61686890934637) 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, 2066409131 + ... + 2066438982.

It is an arithmetic number, because the mean of its divisors is an integer number (6137279449290).

Almost surely, 2^{61686890934638} is an apocalyptic number.

61686890934638 is a deficient number, since it is larger than the sum of its proper divisors (36509580254002).

61686890934638 is a wasteful number, since it uses less digits than its factorization.

61686890934638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4132848571.

The product of its (nonzero) digits is 1934917632, while the sum is 77.

The spelling of 61686890934638 in words is "sixty-one trillion, six hundred eighty-six billion, eight hundred ninety million, nine hundred thirty-four thousand, six hundred thirty-eight".