21155003350 has 48 divisors (see below), whose sum is σ = 42400098720. Its totient is φ = 7806470400.

The previous prime is 21155003333. The next prime is 21155003357. The reversal of 21155003350 is 5330055112.

It is a super-2 number, since 2×21155003350² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21155003357) 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, 1212690 + ... + 1230010.

It is an arithmetic number, because the mean of its divisors is an integer number (883335390).

Almost surely, 2^21155003350 is an apocalyptic number.

21155003350 is an abundant number, since it is smaller than the sum of its proper divisors (21245095370).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21155003350 is a wasteful number, since it uses less digits than its factorization.

21155003350 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19225 (or 19220 counting only the distinct ones).

The product of its (nonzero) digits is 2250, while the sum is 25.

Adding to 21155003350 its reverse (5330055112), we get a palindrome (26485058462).

The spelling of 21155003350 in words is "twenty-one billion, one hundred fifty-five million, three thousand, three hundred fifty".