1242152021 has 8 divisors (see below), whose sum is σ = 1371402144. Its totient is φ = 1115623120.

The previous prime is 1242151993. The next prime is 1242152033. The reversal of 1242152021 is 1202512421.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1242152021 - 2²⁶ = 1175043157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1242151984 and 1242152002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1242152321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 679346 + ... + 681171.

It is an arithmetic number, because the mean of its divisors is an integer number (171425268).

Almost surely, 2^1242152021 is an apocalyptic number.

1242152021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1242152021 is a deficient number, since it is larger than the sum of its proper divisors (129250123).

1242152021 is a wasteful number, since it uses less digits than its factorization.

1242152021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1360611.

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

The square root of 1242152021 is about 35244.1771219020. The cubic root of 1242152021 is about 1074.9582160792.

Adding to 1242152021 its reverse (1202512421), we get a palindrome (2444664442).

The spelling of 1242152021 in words is "one billion, two hundred forty-two million, one hundred fifty-two thousand, twenty-one".