1538247348121 has 27 divisors (see below), whose sum is σ = 1705304556543. Its totient is φ = 1386512577120.

The previous prime is 1538247348103. The next prime is 1538247348167. The reversal of 1538247348121 is 1218437428351.

It is a happy number.

The square root of 1538247348121 is 1240261.

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

It can be written as a sum of positive squares in only one way, i.e., 903573819225 + 634673528896 = 950565^2 + 796664^2 .

It is not a de Polignac number, because 1538247348121 - 2²³ = 1538238959513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1538247346121) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1869072916 + ... + 1869073738.

Almost surely, 2^{1538247348121} is an apocalyptic number.

1538247348121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1538247348121 is the 1240261-st square number.

1538247348121 is the 620131-st centered octagonal number.

It is an amenable number.

1538247348121 is a deficient number, since it is larger than the sum of its proper divisors (167057208422).

1538247348121 is an frugal number, since it uses more digits than its factorization.

1538247348121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1942 (or 971 counting only the distinct ones).

The product of its digits is 1290240, while the sum is 49.

Multiplying 1538247348121 by its sum of digits (49), we get a square (75374120057929 = 8681827²).

The spelling of 1538247348121 in words is "one trillion, five hundred thirty-eight billion, two hundred forty-seven million, three hundred forty-eight thousand, one hundred twenty-one".