16256355421 has 8 divisors (see below), whose sum is σ = 16447181240. Its totient is φ = 16066003968.

The previous prime is 16256355419. The next prime is 16256355443. The reversal of 16256355421 is 12455365261.

It can be written as a sum of positive squares in 4 ways, for example, as 1901919321 + 14354436100 = 43611^2 + 119810^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 16256355421 - 2¹ = 16256355419 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 (16256355481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49416 + ... + 186961.

It is an arithmetic number, because the mean of its divisors is an integer number (2055897655).

Almost surely, 2^16256355421 is an apocalyptic number.

It is an amenable number.

16256355421 is a deficient number, since it is larger than the sum of its proper divisors (190825819).

16256355421 is an equidigital number, since it uses as much as digits as its factorization.

16256355421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237183.

The product of its digits is 216000, while the sum is 40.

The spelling of 16256355421 in words is "sixteen billion, two hundred fifty-six million, three hundred fifty-five thousand, four hundred twenty-one".