1025780121 has 24 divisors (see below), whose sum is σ = 1491764040. Its totient is φ = 679219200.

The previous prime is 1025780071. The next prime is 1025780149. The reversal of 1025780121 is 1210875201.

It can be written as a sum of positive squares in 4 ways, for example, as 254051721 + 771728400 = 15939^2 + 27780^2 .

It is not a de Polignac number, because 1025780121 - 2²³ = 1017391513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1025780191) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1551531 + ... + 1552191.

It is an arithmetic number, because the mean of its divisors is an integer number (62156835).

Almost surely, 2^1025780121 is an apocalyptic number.

It is an amenable number.

1025780121 is a deficient number, since it is larger than the sum of its proper divisors (465983919).

1025780121 is a wasteful number, since it uses less digits than its factorization.

1025780121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1577 (or 1574 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 27.

The square root of 1025780121 is about 32027.8023129905. The cubic root of 1025780121 is about 1008.5205673999.

The spelling of 1025780121 in words is "one billion, twenty-five million, seven hundred eighty thousand, one hundred twenty-one".