11998156564 has 12 divisors (see below), whose sum is σ = 21009899988. Its totient is φ = 5995328000.

The previous prime is 11998156553. The next prime is 11998156567. The reversal of 11998156564 is 46565189911.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 11468696464 + 529460100 = 107092^2 + 23010^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11998156567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 930367 + ... + 943174.

It is an arithmetic number, because the mean of its divisors is an integer number (1750824999).

Almost surely, 2^11998156564 is an apocalyptic number.

It is an amenable number.

11998156564 is a deficient number, since it is larger than the sum of its proper divisors (9011743424).

11998156564 is a wasteful number, since it uses less digits than its factorization.

11998156564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1875146 (or 1875144 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 55.

The spelling of 11998156564 in words is "eleven billion, nine hundred ninety-eight million, one hundred fifty-six thousand, five hundred sixty-four".