1261403450 has 24 divisors (see below), whose sum is σ = 2347696092. Its totient is φ = 504241920.

The previous prime is 1261403449. The next prime is 1261403461. The reversal of 1261403450 is 543041621.

It can be written as a sum of positive squares in 6 ways, for example, as 880724329 + 380679121 = 29677^2 + 19511^2 .

It is a super-2 number, since 2×1261403450² = 3182277327343805000, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81752 + ... + 95948.

Almost surely, 2^1261403450 is an apocalyptic number.

1261403450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1261403450 is a deficient number, since it is larger than the sum of its proper divisors (1086292642).

1261403450 is a wasteful number, since it uses less digits than its factorization.

1261403450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15986 (or 15981 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 1261403450 is about 35516.2420590918. The cubic root of 1261403450 is about 1080.4831657270.

The spelling of 1261403450 in words is "one billion, two hundred sixty-one million, four hundred three thousand, four hundred fifty".