1242251841 has 4 divisors (see below), whose sum is σ = 1656335792. Its totient is φ = 828167892.

The previous prime is 1242251821. The next prime is 1242251867. The reversal of 1242251841 is 1481522421.

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: 1481522421 = 3 ⋅493840807.

It is not a de Polignac number, because 1242251841 - 2¹³ = 1242243649 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1242251799 and 1242251808.

It is not an unprimeable number, because it can be changed into a prime (1242251821) 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, 207041971 + ... + 207041976.

It is an arithmetic number, because the mean of its divisors is an integer number (414083948).

Almost surely, 2^1242251841 is an apocalyptic number.

It is an amenable number.

1242251841 is a deficient number, since it is larger than the sum of its proper divisors (414083951).

1242251841 is an equidigital number, since it uses as much as digits as its factorization.

1242251841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414083950.

The product of its digits is 5120, while the sum is 30.

The square root of 1242251841 is about 35245.5932139041. The cubic root of 1242251841 is about 1074.9870100467.

The spelling of 1242251841 in words is "one billion, two hundred forty-two million, two hundred fifty-one thousand, eight hundred forty-one".