1021540025 has 12 divisors (see below), whose sum is σ = 1381865424. Its totient is φ = 742938000.

The previous prime is 1021539947. The next prime is 1021540049. The reversal of 1021540025 is 5200451201.

It is a de Polignac number, because none of the positive numbers 2^k-1021540025 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021539979 and 1021540006.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1857071 + ... + 1857620.

It is an arithmetic number, because the mean of its divisors is an integer number (115155452).

Almost surely, 2^1021540025 is an apocalyptic number.

It is an amenable number.

1021540025 is a deficient number, since it is larger than the sum of its proper divisors (360325399).

1021540025 is a wasteful number, since it uses less digits than its factorization.

1021540025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3714712 (or 3714707 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 1021540025 is about 31961.5397783023. The cubic root of 1021540025 is about 1007.1290640050.

Adding to 1021540025 its reverse (5200451201), we get a palindrome (6221991226).

The spelling of 1021540025 in words is "one billion, twenty-one million, five hundred forty thousand, twenty-five".