16400620553 has 4 divisors (see below), whose sum is σ = 16400973840. Its totient is φ = 16400267268.

The previous prime is 16400620549. The next prime is 16400620573. The reversal of 16400620553 is 35502600461.

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.

It is a cyclic number.

It is not a de Polignac number, because 16400620553 - 2² = 16400620549 is a prime.

It is a super-3 number, since 3×16400620553³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16400620513) 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, 94175 + ... + 204132.

It is an arithmetic number, because the mean of its divisors is an integer number (4100243460).

Almost surely, 2^16400620553 is an apocalyptic number.

It is an amenable number.

16400620553 is a deficient number, since it is larger than the sum of its proper divisors (353287).

16400620553 is an equidigital number, since it uses as much as digits as its factorization.

16400620553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353286.

The product of its (nonzero) digits is 21600, while the sum is 32.

The spelling of 16400620553 in words is "sixteen billion, four hundred million, six hundred twenty thousand, five hundred fifty-three".