3951541638 has 128 divisors (see below), whose sum is σ = 9953280000. Its totient is φ = 1151615520.

The previous prime is 3951541621. The next prime is 3951541661. The reversal of 3951541638 is 8361451593.

3951541638 is a `hidden beast` number, since 3 + 9 + 5 + 1 + 5 + 4 + 1 + 638 = 666.

It is a super-2 number, since 2×3951541638² = 31229362633695446088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 3951541593 and 3951541602.

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 1645963 + ... + 1648361.

It is an arithmetic number, because the mean of its divisors is an integer number (77760000).

Almost surely, 2^3951541638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3951541638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4976640000).

3951541638 is an abundant number, since it is smaller than the sum of its proper divisors (6001738362).

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

3951541638 is a wasteful number, since it uses less digits than its factorization.

3951541638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2527 (or 2521 counting only the distinct ones).

The product of its digits is 388800, while the sum is 45.

The square root of 3951541638 is about 62861.2888668376. The cubic root of 3951541638 is about 1580.9647526249.

The spelling of 3951541638 in words is "three billion, nine hundred fifty-one million, five hundred forty-one thousand, six hundred thirty-eight".