2564478198 has 64 divisors (see below), whose sum is σ = 5797777920. Its totient is φ = 840049056.

The previous prime is 2564478197. The next prime is 2564478199. The reversal of 2564478198 is 8918744652.

It is a happy number.

2564478198 is a `hidden beast` number, since 2 + 5 + 6 + 447 + 8 + 198 = 666.

It is an interprime number because it is at equal distance from previous prime (2564478197) and next prime (2564478199).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2564478197) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2651511 + ... + 2652477.

It is an arithmetic number, because the mean of its divisors is an integer number (90590280).

Almost surely, 2^2564478198 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2564478198, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2898888960).

2564478198 is an abundant number, since it is smaller than the sum of its proper divisors (3233299722).

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

2564478198 is a wasteful number, since it uses less digits than its factorization.

2564478198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1778 (or 1772 counting only the distinct ones).

The product of its digits is 3870720, while the sum is 54.

The square root of 2564478198 is about 50640.6773058971. The cubic root of 2564478198 is about 1368.7779604722. Note that the first 3 decimals are identical.

The spelling of 2564478198 in words is "two billion, five hundred sixty-four million, four hundred seventy-eight thousand, one hundred ninety-eight".