18621699057 has 24 divisors (see below), whose sum is σ = 28984870824. Its totient is φ = 11452472064.

The previous prime is 18621699053. The next prime is 18621699077. The reversal of 18621699057 is 75099612681.

18621699057 is a `hidden beast` number, since 1 + 8 + 621 + 6 + 9 + 9 + 0 + 5 + 7 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 28740321 + 18592958736 = 5361^2 + 136356^2 .

It is not a de Polignac number, because 18621699057 - 2² = 18621699053 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18621698994 and 18621699012.

It is not an unprimeable number, because it can be changed into a prime (18621699053) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 145843 + ... + 241895.

It is an arithmetic number, because the mean of its divisors is an integer number (1207702951).

Almost surely, 2^18621699057 is an apocalyptic number.

It is an amenable number.

18621699057 is a deficient number, since it is larger than the sum of its proper divisors (10363171767).

18621699057 is a wasteful number, since it uses less digits than its factorization.

18621699057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97729 (or 97726 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 54.

The spelling of 18621699057 in words is "eighteen billion, six hundred twenty-one million, six hundred ninety-nine thousand, fifty-seven".