1247667421 has 32 divisors (see below), whose sum is σ = 1689198336. Its totient is φ = 897336000.

The previous prime is 1247667419. The next prime is 1247667427.

1247667421 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1247667421 - 2¹ = 1247667419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1247667427) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 115971 + ... + 126271.

It is an arithmetic number, because the mean of its divisors is an integer number (52787448).

Almost surely, 2^1247667421 is an apocalyptic number.

1247667421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1247667421 is a deficient number, since it is larger than the sum of its proper divisors (441530915).

1247667421 is a wasteful number, since it uses less digits than its factorization.

1247667421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10354 (or 10332 counting only the distinct ones).

The product of its digits is 112896, while the sum is 40.

The square root of 1247667421 is about 35322.3360071216. The cubic root of 1247667421 is about 1076.5468759150.

It can be divided in two parts, 12476 and 67421, that added together give a palindrome (79897).

The spelling of 1247667421 in words is "one billion, two hundred forty-seven million, six hundred sixty-seven thousand, four hundred twenty-one".