1306628557 has 8 divisors (see below), whose sum is σ = 1433688984. Its totient is φ = 1183361088.

The previous prime is 1306628539. The next prime is 1306628567. The reversal of 1306628557 is 7558266031.

It can be written as a sum of positive squares in 4 ways, for example, as 1179396 + 1305449161 = 1086^2 + 36131^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1306628557 - 2¹⁵ = 1306595789 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1306628527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 947518 + ... + 948895.

It is an arithmetic number, because the mean of its divisors is an integer number (179211123).

Almost surely, 2^1306628557 is an apocalyptic number.

It is an amenable number.

1306628557 is a deficient number, since it is larger than the sum of its proper divisors (127060427).

1306628557 is a wasteful number, since it uses less digits than its factorization.

1306628557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1896479.

The product of its (nonzero) digits is 302400, while the sum is 43.

The square root of 1306628557 is about 36147.3174246721. The cubic root of 1306628557 is about 1093.2447032949.

The spelling of 1306628557 in words is "one billion, three hundred six million, six hundred twenty-eight thousand, five hundred fifty-seven".