21030220240 has 40 divisors (see below), whose sum is σ = 48906019368. Its totient is φ = 8410237440.

The previous prime is 21030220217. The next prime is 21030220273. The reversal of 21030220240 is 4202203012.

It can be written as a sum of positive squares in 4 ways, for example, as 4493289024 + 16536931216 = 67032^2 + 128596^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 371410 + ... + 424270.

Almost surely, 2^21030220240 is an apocalyptic number.

21030220240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21030220240 is an abundant number, since it is smaller than the sum of its proper divisors (27875799128).

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

21030220240 is a wasteful number, since it uses less digits than its factorization.

21030220240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57847 (or 57841 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

Adding to 21030220240 its reverse (4202203012), we get a palindrome (25232423252).

The spelling of 21030220240 in words is "twenty-one billion, thirty million, two hundred twenty thousand, two hundred forty".