1525252621 has 2 divisors, whose sum is σ = 1525252622. Its totient is φ = 1525252620.

The previous prime is 1525252537. The next prime is 1525252633. The reversal of 1525252621 is 1262525251.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1224230121 + 301022500 = 34989^2 + 17350^2 .

It is a cyclic number.

It is not a de Polignac number, because 1525252621 - 2⁹ = 1525252109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1525252691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 762626310 + 762626311.

It is an arithmetic number, because the mean of its divisors is an integer number (762626311).

Almost surely, 2^1525252621 is an apocalyptic number.

It is an amenable number.

1525252621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1525252621 is an equidigital number, since it uses as much as digits as its factorization.

1525252621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12000, while the sum is 31.

The square root of 1525252621 is about 39054.4827260585. The cubic root of 1525252621 is about 1151.1023131909.

Adding to 1525252621 its reverse (1262525251), we get a palindrome (2787777872).

The spelling of 1525252621 in words is "one billion, five hundred twenty-five million, two hundred fifty-two thousand, six hundred twenty-one".