1988043521 has 4 divisors (see below), whose sum is σ = 1988410032. Its totient is φ = 1987677012.

The previous prime is 1988043509. The next prime is 1988043557. The reversal of 1988043521 is 1253408891.

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 1988043521 - 2⁶ = 1988043457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1988943521) 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, 174995 + ... + 186008.

It is an arithmetic number, because the mean of its divisors is an integer number (497102508).

Almost surely, 2^1988043521 is an apocalyptic number.

It is an amenable number.

1988043521 is a deficient number, since it is larger than the sum of its proper divisors (366511).

1988043521 is an equidigital number, since it uses as much as digits as its factorization.

1988043521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366510.

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 1988043521 is about 44587.4816624577. The cubic root of 1988043521 is about 1257.4053267539.

The spelling of 1988043521 in words is "one billion, nine hundred eighty-eight million, forty-three thousand, five hundred twenty-one".