21155145003 has 16 divisors (see below), whose sum is σ = 31350222240. Its totient is φ = 14099260032.

The previous prime is 21155144951. The next prime is 21155145013. The reversal of 21155145003 is 30054155112.

21155145003 is a `hidden beast` number, since 2 + 1 + 155 + 1 + 4 + 500 + 3 = 666.

It is not a de Polignac number, because 21155145003 - 2²⁶ = 21088036139 is a prime.

It is a super-3 number, since 3×21155145003³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21155145013) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21426 + ... + 206807.

It is an arithmetic number, because the mean of its divisors is an integer number (1959388890).

Almost surely, 2^21155145003 is an apocalyptic number.

21155145003 is a deficient number, since it is larger than the sum of its proper divisors (10195077237).

21155145003 is a wasteful number, since it uses less digits than its factorization.

21155145003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231675 (or 231669 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The spelling of 21155145003 in words is "twenty-one billion, one hundred fifty-five million, one hundred forty-five thousand, three".