16561950031 has 4 divisors (see below), whose sum is σ = 18067581864. Its totient is φ = 15056318200.

The previous prime is 16561950029. The next prime is 16561950037. The reversal of 16561950031 is 13005916561.

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

It is not a de Polignac number, because 16561950031 - 2¹ = 16561950029 is a prime.

It is a super-2 number, since 2×16561950031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16561950037) 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, 752815900 + ... + 752815921.

It is an arithmetic number, because the mean of its divisors is an integer number (4516895466).

Almost surely, 2^16561950031 is an apocalyptic number.

16561950031 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

16561950031 is a deficient number, since it is larger than the sum of its proper divisors (1505631833).

16561950031 is a wasteful number, since it uses less digits than its factorization.

16561950031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1505631832.

The product of its (nonzero) digits is 24300, while the sum is 37.

The spelling of 16561950031 in words is "sixteen billion, five hundred sixty-one million, nine hundred fifty thousand, thirty-one".