1620420525 has 24 divisors (see below), whose sum is σ = 2976773760. Its totient is φ = 864223920.

The previous prime is 1620420517. The next prime is 1620420547. The reversal of 1620420525 is 5250240261.

It is not a de Polignac number, because 1620420525 - 2³ = 1620420517 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1199637 + ... + 1200986.

It is an arithmetic number, because the mean of its divisors is an integer number (124032240).

Almost surely, 2^1620420525 is an apocalyptic number.

1620420525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1620420525 is a deficient number, since it is larger than the sum of its proper divisors (1356353235).

1620420525 is a wasteful number, since it uses less digits than its factorization.

1620420525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2400642 (or 2400631 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 1620420525 is about 40254.4472698359. The cubic root of 1620420525 is about 1174.5619069979.

Adding to 1620420525 its reverse (5250240261), we get a palindrome (6870660786).

The spelling of 1620420525 in words is "one billion, six hundred twenty million, four hundred twenty thousand, five hundred twenty-five".