1213640477 has 6 divisors (see below), whose sum is σ = 1411785918. Its totient is φ = 1040263224.

The previous prime is 1213640431. The next prime is 1213640497. The reversal of 1213640477 is 7740463121.

It can be written as a sum of positive squares in only one way, i.e., 1099983556 + 113656921 = 33166^2 + 10661^2 .

It is not a de Polignac number, because 1213640477 - 2⁶ = 1213640413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213640497) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12384038 + ... + 12384135.

It is an arithmetic number, because the mean of its divisors is an integer number (235297653).

Almost surely, 2^1213640477 is an apocalyptic number.

It is an amenable number.

1213640477 is a deficient number, since it is larger than the sum of its proper divisors (198145441).

1213640477 is an equidigital number, since it uses as much as digits as its factorization.

1213640477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24768187 (or 24768180 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 35.

The square root of 1213640477 is about 34837.3431392235. The cubic root of 1213640477 is about 1066.6698445977.

The spelling of 1213640477 in words is "one billion, two hundred thirteen million, six hundred forty thousand, four hundred seventy-seven".