1021251604 has 12 divisors (see below), whose sum is σ = 1811672884. Its totient is φ = 503630784.

The previous prime is 1021251563. The next prime is 1021251611. The reversal of 1021251604 is 4061521201.

It can be written as a sum of positive squares in 2 ways, for example, as 325874704 + 695376900 = 18052^2 + 26370^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1748427 + ... + 1749010.

Almost surely, 2^1021251604 is an apocalyptic number.

It is an amenable number.

1021251604 is a deficient number, since it is larger than the sum of its proper divisors (790421280).

1021251604 is a wasteful number, since it uses less digits than its factorization.

1021251604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3497514 (or 3497512 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 1021251604 is about 31957.0274587609. The cubic root of 1021251604 is about 1007.0342710105.

Adding to 1021251604 its reverse (4061521201), we get a palindrome (5082772805).

It can be divided in two parts, 10212 and 51604, that added together give a palindrome (61816).

The spelling of 1021251604 in words is "one billion, twenty-one million, two hundred fifty-one thousand, six hundred four".