20101521040 has 20 divisors (see below), whose sum is σ = 46736036604. Its totient is φ = 8040608384.

The previous prime is 20101521031. The next prime is 20101521049. The reversal of 20101521040 is 4012510102.

It is an interprime number because it is at equal distance from previous prime (20101521031) and next prime (20101521049).

It can be written as a sum of positive squares in 2 ways, for example, as 2580233616 + 17521287424 = 50796^2 + 132368^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×20101521040² (a number of 21 digits) contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (20101521049) 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, 125634427 + ... + 125634586.

Almost surely, 2^20101521040 is an apocalyptic number.

20101521040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20101521040 is an abundant number, since it is smaller than the sum of its proper divisors (26634515564).

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

20101521040 is a wasteful number, since it uses less digits than its factorization.

20101521040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251269026 (or 251269020 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The spelling of 20101521040 in words is "twenty billion, one hundred one million, five hundred twenty-one thousand, forty".