1988542764649 has 9 divisors (see below), whose sum is σ = 2313214290621. Its totient is φ = 1704456765900.

The previous prime is 1988542764647. The next prime is 1988542764697. The reversal of 1988542764649 is 9464672458891.

The square root of 1988542764649 is 1410157.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 1988542764649 - 2¹ = 1988542764647 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1988542764643) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9770374 + ... + 9971824.

It is an arithmetic number, because the mean of its divisors is an integer number (257023810069).

Almost surely, 2^{1988542764649} is an apocalyptic number.

1988542764649 is the 1410157-th square number.

1988542764649 is the 705079-th centered octagonal number.

It is an amenable number.

1988542764649 is a deficient number, since it is larger than the sum of its proper divisors (324671525972).

1988542764649 is an frugal number, since it uses more digits than its factorization.

1988542764649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402916 (or 201458 counting only the distinct ones).

The product of its digits is 836075520, while the sum is 73.

The spelling of 1988542764649 in words is "one trillion, nine hundred eighty-eight billion, five hundred forty-two million, seven hundred sixty-four thousand, six hundred forty-nine".