1623440653 has 4 divisors (see below), whose sum is σ = 1718937180. Its totient is φ = 1527944128.

The previous prime is 1623440647. The next prime is 1623440657. The reversal of 1623440653 is 3560443261.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3560443261 = 953 ⋅3736037.

It can be written as a sum of positive squares in 2 ways, for example, as 1045422889 + 578017764 = 32333^2 + 24042^2 .

It is a cyclic number.

It is not a de Polignac number, because 1623440653 - 2¹⁷ = 1623309581 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 (1623440657) 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, 47748238 + ... + 47748271.

It is an arithmetic number, because the mean of its divisors is an integer number (429734295).

Almost surely, 2^1623440653 is an apocalyptic number.

It is an amenable number.

1623440653 is a deficient number, since it is larger than the sum of its proper divisors (95496527).

1623440653 is an equidigital number, since it uses as much as digits as its factorization.

1623440653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95496526.

The product of its (nonzero) digits is 51840, while the sum is 34.

The square root of 1623440653 is about 40291.9427801639. The cubic root of 1623440653 is about 1175.2911674377.

The spelling of 1623440653 in words is "one billion, six hundred twenty-three million, four hundred forty thousand, six hundred fifty-three".