1621021425 has 12 divisors (see below), whose sum is σ = 2680088880. Its totient is φ = 864544720.

The previous prime is 1621021357. The next prime is 1621021463. The reversal of 1621021425 is 5241201261.

1621021425 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1621021425 - 2¹⁴ = 1621005041 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1621021395 and 1621021404.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10806735 + ... + 10806884.

It is an arithmetic number, because the mean of its divisors is an integer number (223340740).

Almost surely, 2^1621021425 is an apocalyptic number.

1621021425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1621021425 is a deficient number, since it is larger than the sum of its proper divisors (1059067455).

1621021425 is a wasteful number, since it uses less digits than its factorization.

1621021425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21613632 (or 21613627 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 1621021425 is about 40261.9103496096. The cubic root of 1621021425 is about 1174.7070765210.

Adding to 1621021425 its reverse (5241201261), we get a palindrome (6862222686).

The spelling of 1621021425 in words is "one billion, six hundred twenty-one million, twenty-one thousand, four hundred twenty-five".