1266656538 has 32 divisors (see below), whose sum is σ = 2904494976. Its totient is φ = 360741888.

The previous prime is 1266656513. The next prime is 1266656539. The reversal of 1266656538 is 8356566621.

It is not an unprimeable number, because it can be changed into a prime (1266656539) 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, 35031 + ... + 61322.

It is an arithmetic number, because the mean of its divisors is an integer number (90765468).

Almost surely, 2^1266656538 is an apocalyptic number.

1266656538 is an abundant number, since it is smaller than the sum of its proper divisors (1637838438).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1266656538 is a wasteful number, since it uses less digits than its factorization.

1266656538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96678.

The product of its digits is 1555200, while the sum is 48.

The square root of 1266656538 is about 35590.1185443376. The cubic root of 1266656538 is about 1081.9809715540.

The spelling of 1266656538 in words is "one billion, two hundred sixty-six million, six hundred fifty-six thousand, five hundred thirty-eight".