1245775421 has 16 divisors (see below), whose sum is σ = 1392787968. Its totient is φ = 1104721200.

The previous prime is 1245775357. The next prime is 1245775423.

It is a happy number.

1245775421 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1245775421 - 2⁶ = 1245775357 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1245775423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67706 + ... + 84116.

It is an arithmetic number, because the mean of its divisors is an integer number (87049248).

Almost surely, 2^1245775421 is an apocalyptic number.

1245775421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1245775421 is a deficient number, since it is larger than the sum of its proper divisors (147012547).

1245775421 is a wasteful number, since it uses less digits than its factorization.

1245775421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16592.

The product of its digits is 78400, while the sum is 38.

The square root of 1245775421 is about 35295.5439255439. The cubic root of 1245775421 is about 1076.0024313802.

It can be divided in two parts, 12457 and 75421, that added together give a palindrome (87878).

The spelling of 1245775421 in words is "one billion, two hundred forty-five million, seven hundred seventy-five thousand, four hundred twenty-one".