1620465553 has 8 divisors (see below), whose sum is σ = 1852307072. Its totient is φ = 1388710656.

The previous prime is 1620465547. The next prime is 1620465563. The reversal of 1620465553 is 3555640261.

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 1620465553 - 2²⁹ = 1083594641 is a prime.

It is a super-3 number, since 3×1620465553³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1620465533) 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, 25201 + ... + 62257.

It is an arithmetic number, because the mean of its divisors is an integer number (231538384).

Almost surely, 2^1620465553 is an apocalyptic number.

It is an amenable number.

1620465553 is a deficient number, since it is larger than the sum of its proper divisors (231841519).

1620465553 is an equidigital number, since it uses as much as digits as its factorization.

1620465553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43311.

The product of its (nonzero) digits is 108000, while the sum is 37.

The square root of 1620465553 is about 40255.0065581910. The cubic root of 1620465553 is about 1174.5727864132.

The spelling of 1620465553 in words is "one billion, six hundred twenty million, four hundred sixty-five thousand, five hundred fifty-three".