16356005021 has 4 divisors (see below), whose sum is σ = 16357740000. Its totient is φ = 16354270044.

The previous prime is 16356004961. The next prime is 16356005023. The reversal of 16356005021 is 12050065361.

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: 12050065361 = 173 ⋅69653557.

It is a cyclic number.

It is not a de Polignac number, because 16356005021 - 2¹⁸ = 16355742877 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 (16356005023) 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, 853271 + ... + 872228.

It is an arithmetic number, because the mean of its divisors is an integer number (4089435000).

Almost surely, 2^16356005021 is an apocalyptic number.

It is an amenable number.

16356005021 is a deficient number, since it is larger than the sum of its proper divisors (1734979).

16356005021 is an equidigital number, since it uses as much as digits as its factorization.

16356005021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1734978.

The product of its (nonzero) digits is 5400, while the sum is 29.

The spelling of 16356005021 in words is "sixteen billion, three hundred fifty-six million, five thousand, twenty-one".