1653072821 has 4 divisors (see below), whose sum is σ = 1653180000. Its totient is φ = 1652965644.

The previous prime is 1653072803. The next prime is 1653072823. The reversal of 1653072821 is 1282703561.

It is a happy number.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1653072821 - 2²⁶ = 1585963957 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 (1653072823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25571 + ... + 62928.

It is an arithmetic number, because the mean of its divisors is an integer number (413295000).

Almost surely, 2^1653072821 is an apocalyptic number.

It is an amenable number.

1653072821 is a deficient number, since it is larger than the sum of its proper divisors (107179).

1653072821 is an equidigital number, since it uses as much as digits as its factorization.

1653072821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107178.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 1653072821 is about 40657.9982414285. The cubic root of 1653072821 is about 1182.3988404897.

The spelling of 1653072821 in words is "one billion, six hundred fifty-three million, seventy-two thousand, eight hundred twenty-one".