66655754638 has 8 divisors (see below), whose sum is σ = 109073053080. Its totient is φ = 30298070280.

The previous prime is 66655754621. The next prime is 66655754653. The reversal of 66655754638 is 83645755666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×66655754638² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1514903493 + ... + 1514903536.

It is an arithmetic number, because the mean of its divisors is an integer number (13634131635).

Almost surely, 2^66655754638 is an apocalyptic number.

66655754638 is a deficient number, since it is larger than the sum of its proper divisors (42417298442).

66655754638 is a wasteful number, since it uses less digits than its factorization.

66655754638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3029807042.

The product of its digits is 108864000, while the sum is 61.

The spelling of 66655754638 in words is "sixty-six billion, six hundred fifty-five million, seven hundred fifty-four thousand, six hundred thirty-eight".