1405242251 has 4 divisors (see below), whose sum is σ = 1605991152. Its totient is φ = 1204493352.

The previous prime is 1405242239. The next prime is 1405242257. The reversal of 1405242251 is 1522425041.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1522425041 = 521 ⋅2922121.

It is a cyclic number.

It is not a de Polignac number, because 1405242251 - 2⁶ = 1405242187 is a prime.

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 1405242251.

It is not an unprimeable number, because it can be changed into a prime (1405242257) 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, 100374440 + ... + 100374453.

It is an arithmetic number, because the mean of its divisors is an integer number (401497788).

Almost surely, 2^1405242251 is an apocalyptic number.

1405242251 is a deficient number, since it is larger than the sum of its proper divisors (200748901).

1405242251 is an equidigital number, since it uses as much as digits as its factorization.

1405242251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200748900.

The product of its (nonzero) digits is 3200, while the sum is 26.

The square root of 1405242251 is about 37486.5609385550. The cubic root of 1405242251 is about 1120.0835000990.

Adding to 1405242251 its reverse (1522425041), we get a palindrome (2927667292).

The spelling of 1405242251 in words is "one billion, four hundred five million, two hundred forty-two thousand, two hundred fifty-one".