1621023420 has 96 divisors (see below), whose sum is σ = 4677378048. Its totient is φ = 419249152.

The previous prime is 1621023419. The next prime is 1621023433. The reversal of 1621023420 is 243201261.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 316117 + ... + 321203.

It is an arithmetic number, because the mean of its divisors is an integer number (48722688).

Almost surely, 2^1621023420 is an apocalyptic number.

1621023420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1621023420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2338689024).

1621023420 is an abundant number, since it is smaller than the sum of its proper divisors (3056354628).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1621023420 is a wasteful number, since it uses less digits than its factorization.

1621023420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5259 (or 5257 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 1621023420 is about 40261.9351248794. The cubic root of 1621023420 is about 1174.7075584270.

Adding to 1621023420 its reverse (243201261), we get a palindrome (1864224681).

The spelling of 1621023420 in words is "one billion, six hundred twenty-one million, twenty-three thousand, four hundred twenty".