2540307779478 has 80 divisors (see below), whose sum is σ = 6729660542880. Its totient is φ = 700774550784.

The previous prime is 2540307779437. The next prime is 2540307779479. The reversal of 2540307779478 is 8749777030452.

2540307779478 is a `hidden beast` number, since 2 + 5 + 403 + 0 + 7 + 77 + 94 + 78 = 666.

It is a super-2 number, since 2×2540307779478² (a number of 26 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2540307779479) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 38590051 + ... + 38655822.

It is an arithmetic number, because the mean of its divisors is an integer number (84120756786).

Almost surely, 2^{2540307779478} is an apocalyptic number.

2540307779478 is an abundant number, since it is smaller than the sum of its proper divisors (4189352763402).

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

2540307779478 is a wasteful number, since it uses less digits than its factorization.

2540307779478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77245923 (or 77245914 counting only the distinct ones).

The product of its (nonzero) digits is 82978560, while the sum is 63.

The spelling of 2540307779478 in words is "two trillion, five hundred forty billion, three hundred seven million, seven hundred seventy-nine thousand, four hundred seventy-eight".