16551537901 has 4 divisors (see below), whose sum is σ = 16564359904. Its totient is φ = 16538715900.

The previous prime is 16551537881. The next prime is 16551537917. The reversal of 16551537901 is 10973515561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10973515561 = 41 ⋅267646721.

It is a cyclic number.

It is not a de Polignac number, because 16551537901 - 2⁹ = 16551537389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16551537991) 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, 6409065 + ... + 6411646.

It is an arithmetic number, because the mean of its divisors is an integer number (4141089976).

Almost surely, 2^16551537901 is an apocalyptic number.

It is an amenable number.

16551537901 is a deficient number, since it is larger than the sum of its proper divisors (12822003).

16551537901 is a wasteful number, since it uses less digits than its factorization.

16551537901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12822002.

The product of its (nonzero) digits is 141750, while the sum is 43.

The spelling of 16551537901 in words is "sixteen billion, five hundred fifty-one million, five hundred thirty-seven thousand, nine hundred one".