21123120130 has 64 divisors (see below), whose sum is σ = 44123512320. Its totient is φ = 7130847744.

The previous prime is 21123120119. The next prime is 21123120131. The reversal of 21123120130 is 3102132112.

It is a super-2 number, since 2×21123120130² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21123120131) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3302976 + ... + 3309364.

It is an arithmetic number, because the mean of its divisors is an integer number (689429880).

Almost surely, 2^21123120130 is an apocalyptic number.

21123120130 is an abundant number, since it is smaller than the sum of its proper divisors (23000392190).

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

21123120130 is a wasteful number, since it uses less digits than its factorization.

21123120130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7123.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21123120130 its reverse (3102132112), we get a palindrome (24225252242).

It can be divided in two parts, 211231 and 20130, that added together give a square (231361 = 481²).

The spelling of 21123120130 in words is "twenty-one billion, one hundred twenty-three million, one hundred twenty thousand, one hundred thirty".