1621425136 has 20 divisors (see below), whose sum is σ = 3151557712. Its totient is φ = 808119936.

The previous prime is 1621425109. The next prime is 1621425163. The reversal of 1621425136 is 6315241261.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1621425109) and next prime (1621425163).

It is a junction number, because it is equal to n+sod(n) for n = 1621425098 and 1621425107.

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, 156876 + ... + 166891.

Almost surely, 2^1621425136 is an apocalyptic number.

1621425136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1621425136 is a deficient number, since it is larger than the sum of its proper divisors (1530132576).

1621425136 is a wasteful number, since it uses less digits than its factorization.

1621425136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324088 (or 324082 counting only the distinct ones).

The product of its digits is 8640, while the sum is 31.

The square root of 1621425136 is about 40266.9235974143. The cubic root of 1621425136 is about 1174.8045876329.

Adding to 1621425136 its reverse (6315241261), we get a palindrome (7936666397).

The spelling of 1621425136 in words is "one billion, six hundred twenty-one million, four hundred twenty-five thousand, one hundred thirty-six".