20161991742 has 8 divisors (see below), whose sum is σ = 40323983496. Its totient is φ = 6720663912.

The previous prime is 20161991741. The next prime is 20161991743. The reversal of 20161991742 is 24719916102.

It is an interprime number because it is at equal distance from previous prime (20161991741) and next prime (20161991743).

It is a sphenic number, since it is the product of 3 distinct primes.

20161991742 is an admirable number.

It is a super-2 number, since 2×20161991742² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20161991694 and 20161991703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20161991741) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1680165973 + ... + 1680165984.

It is an arithmetic number, because the mean of its divisors is an integer number (5040497937).

Almost surely, 2^20161991742 is an apocalyptic number.

20161991742 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20161991742 is a wasteful number, since it uses less digits than its factorization.

20161991742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3360331962.

The product of its (nonzero) digits is 54432, while the sum is 42.

The spelling of 20161991742 in words is "twenty billion, one hundred sixty-one million, nine hundred ninety-one thousand, seven hundred forty-two".