1261864 has 8 divisors (see below), whose sum is σ = 2366010. Its totient is φ = 630928.

The previous prime is 1261861. The next prime is 1261889. The reversal of 1261864 is 4681621.

It can be written as a sum of positive squares in only one way, i.e., 1144900 + 116964 = 1070^2 + 342^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1261861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78859 + ... + 78874.

2^1261864 is an apocalyptic number.

It is an amenable number.

1261864 is a deficient number, since it is larger than the sum of its proper divisors (1104146).

1261864 is a wasteful number, since it uses less digits than its factorization.

1261864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157739 (or 157735 counting only the distinct ones).

The product of its digits is 2304, while the sum is 28.

The square root of 1261864 is about 1123.3272007746. The cubic root of 1261864 is about 108.0614647840.

The spelling of 1261864 in words is "one million, two hundred sixty-one thousand, eight hundred sixty-four".