16861899550 has 24 divisors (see below), whose sum is σ = 31640693616. Its totient is φ = 6685069440.

The previous prime is 16861899517. The next prime is 16861899623. The reversal of 16861899550 is 5599816861.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1486554 + ... + 1497853.

It is an arithmetic number, because the mean of its divisors is an integer number (1318362234).

Almost surely, 2^16861899550 is an apocalyptic number.

16861899550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16861899550 is a deficient number, since it is larger than the sum of its proper divisors (14778794066).

16861899550 is a wasteful number, since it uses less digits than its factorization.

16861899550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2984532 (or 2984527 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 58.

The spelling of 16861899550 in words is "sixteen billion, eight hundred sixty-one million, eight hundred ninety-nine thousand, five hundred fifty".