55641768778 has 32 divisors (see below), whose sum is σ = 86687133120. Its totient is φ = 26754000000.

The previous prime is 55641768739. The next prime is 55641768781. The reversal of 55641768778 is 87786714655.

It is a super-2 number, since 2×55641768778² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17113653 + ... + 17116903.

It is an arithmetic number, because the mean of its divisors is an integer number (2708972910).

Almost surely, 2^55641768778 is an apocalyptic number.

55641768778 is a gapful number since it is divisible by the number (58) formed by its first and last digit.

55641768778 is a deficient number, since it is larger than the sum of its proper divisors (31045364342).

55641768778 is a wasteful number, since it uses less digits than its factorization.

55641768778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4374.

The product of its digits is 79027200, while the sum is 64.

The spelling of 55641768778 in words is "fifty-five billion, six hundred forty-one million, seven hundred sixty-eight thousand, seven hundred seventy-eight".