1240891478 has 4 divisors (see below), whose sum is σ = 1861337220. Its totient is φ = 620445738.

The previous prime is 1240891471. The next prime is 1240891493. The reversal of 1240891478 is 8741980421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8741980421 = 191 ⋅45769531.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1240891471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310222868 + ... + 310222871.

It is an arithmetic number, because the mean of its divisors is an integer number (465334305).

Almost surely, 2^1240891478 is an apocalyptic number.

1240891478 is a deficient number, since it is larger than the sum of its proper divisors (620445742).

1240891478 is an equidigital number, since it uses as much as digits as its factorization.

1240891478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 620445741.

The product of its (nonzero) digits is 129024, while the sum is 44.

The square root of 1240891478 is about 35226.2895860464. The cubic root of 1240891478 is about 1074.5944684180.

The spelling of 1240891478 in words is "one billion, two hundred forty million, eight hundred ninety-one thousand, four hundred seventy-eight".