19986706542 has 64 divisors (see below), whose sum is σ = 44387481600. Its totient is φ = 5948419680.

The previous prime is 19986706541. The next prime is 19986706559. The reversal of 19986706542 is 24560768991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19986706541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6489759 + ... + 6492837.

It is an arithmetic number, because the mean of its divisors is an integer number (693554400).

Almost surely, 2^19986706542 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19986706542, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22193740800).

19986706542 is an abundant number, since it is smaller than the sum of its proper divisors (24400775058).

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

19986706542 is a wasteful number, since it uses less digits than its factorization.

19986706542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4821.

The product of its (nonzero) digits is 6531840, while the sum is 57.

The spelling of 19986706542 in words is "nineteen billion, nine hundred eighty-six million, seven hundred six thousand, five hundred forty-two".