1012400020 has 12 divisors (see below), whose sum is σ = 2126040084. Its totient is φ = 404960000.

The previous prime is 1012399991. The next prime is 1012400023. The reversal of 1012400020 is 200042101.

It can be written as a sum of positive squares in 2 ways, for example, as 476199684 + 536200336 = 21822^2 + 23156^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1012400023) 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, 25309981 + ... + 25310020.

It is an arithmetic number, because the mean of its divisors is an integer number (177170007).

Almost surely, 2^1012400020 is an apocalyptic number.

1012400020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1012400020 is an abundant number, since it is smaller than the sum of its proper divisors (1113640064).

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

1012400020 is a wasteful number, since it uses less digits than its factorization.

1012400020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50620010 (or 50620008 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 1012400020 is about 31818.2340804766. The cubic root of 1012400020 is about 1004.1163722297.

Adding to 1012400020 its reverse (200042101), we get a palindrome (1212442121).

The spelling of 1012400020 in words is "one billion, twelve million, four hundred thousand, twenty".