1247427994 has 4 divisors (see below), whose sum is σ = 1871141994. Its totient is φ = 623713996.

The previous prime is 1247427971. The next prime is 1247427997. The reversal of 1247427994 is 4997247421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4997247421 = 23 ⋅217271627.

It can be written as a sum of positive squares in only one way, i.e., 807980625 + 439447369 = 28425^2 + 20963^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (1247427997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 311856997 + ... + 311857000.

Almost surely, 2^1247427994 is an apocalyptic number.

1247427994 is a deficient number, since it is larger than the sum of its proper divisors (623714000).

1247427994 is an equidigital number, since it uses as much as digits as its factorization.

1247427994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 623713999.

The product of its digits is 1016064, while the sum is 49.

The square root of 1247427994 is about 35318.9466717228. The cubic root of 1247427994 is about 1076.4780085031.

It can be divided in two parts, 1247427 and 994, that added together give a palindrome (1248421).

The spelling of 1247427994 in words is "one billion, two hundred forty-seven million, four hundred twenty-seven thousand, nine hundred ninety-four".