1993724621 has 4 divisors (see below), whose sum is σ = 2278542432. Its totient is φ = 1708906812.

The previous prime is 1993724611. The next prime is 1993724633. The reversal of 1993724621 is 1264273991.

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 1993724621 - 2¹⁴ = 1993708237 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 (1993724611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 142408895 + ... + 142408908.

It is an arithmetic number, because the mean of its divisors is an integer number (569635608).

Almost surely, 2^1993724621 is an apocalyptic number.

It is an amenable number.

1993724621 is a deficient number, since it is larger than the sum of its proper divisors (284817811).

1993724621 is an equidigital number, since it uses as much as digits as its factorization.

1993724621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284817810.

The product of its digits is 163296, while the sum is 44.

The square root of 1993724621 is about 44651.1435575843. The cubic root of 1993724621 is about 1258.6019222440.

The spelling of 1993724621 in words is "one billion, nine hundred ninety-three million, seven hundred twenty-four thousand, six hundred twenty-one".