1542410021 has 4 divisors (see below), whose sum is σ = 1544668992. Its totient is φ = 1540151052.

The previous prime is 1542410011. The next prime is 1542410039. The reversal of 1542410021 is 1200142451.

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 an emirpimes, since its reverse is a distinct semiprime: 1200142451 = 3727 ⋅322013.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1542410021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1542409975 and 1542410002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1542410011) 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, 1128461 + ... + 1129826.

It is an arithmetic number, because the mean of its divisors is an integer number (386167248).

Almost surely, 2^1542410021 is an apocalyptic number.

It is an amenable number.

1542410021 is a deficient number, since it is larger than the sum of its proper divisors (2258971).

1542410021 is an equidigital number, since it uses as much as digits as its factorization.

1542410021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2258970.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 1542410021 is about 39273.5282474086. The cubic root of 1542410021 is about 1155.4024374250.

Adding to 1542410021 its reverse (1200142451), we get a palindrome (2742552472).

The spelling of 1542410021 in words is "one billion, five hundred forty-two million, four hundred ten thousand, twenty-one".