1242651421 has 8 divisors (see below), whose sum is σ = 1402365600. Its totient is φ = 1090728240.

The previous prime is 1242651419. The next prime is 1242651437. The reversal of 1242651421 is 1241562421.

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 1242651421 - 2¹ = 1242651419 is a prime.

It is a super-2 number, since 2×1242651421² = 3088365108226638482, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1242651421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1242657421) 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, 1947411 + ... + 1948048.

It is an arithmetic number, because the mean of its divisors is an integer number (175295700).

Almost surely, 2^1242651421 is an apocalyptic number.

1242651421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1242651421 is a deficient number, since it is larger than the sum of its proper divisors (159714179).

1242651421 is a wasteful number, since it uses less digits than its factorization.

1242651421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3895499.

The product of its digits is 3840, while the sum is 28.

The square root of 1242651421 is about 35251.2612682156. The cubic root of 1242651421 is about 1075.1022570115.

The spelling of 1242651421 in words is "one billion, two hundred forty-two million, six hundred fifty-one thousand, four hundred twenty-one".