1020400051 has 4 divisors (see below), whose sum is σ = 1113163704. Its totient is φ = 927636400.

The previous prime is 1020400039. The next prime is 1020400067. The reversal of 1020400051 is 1500040201.

1020400051 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1020400051 - 2¹¹ = 1020398003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1020400021) 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, 46381810 + ... + 46381831.

It is an arithmetic number, because the mean of its divisors is an integer number (278290926).

Almost surely, 2^1020400051 is an apocalyptic number.

1020400051 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1020400051 is a deficient number, since it is larger than the sum of its proper divisors (92763653).

1020400051 is an equidigital number, since it uses as much as digits as its factorization.

1020400051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92763652.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 1020400051 is about 31943.7012727079. The cubic root of 1020400051 is about 1006.7542938038.

Adding to 1020400051 its reverse (1500040201), we get a palindrome (2520440252).

The spelling of 1020400051 in words is "one billion, twenty million, four hundred thousand, fifty-one".