1621540430 has 16 divisors (see below), whose sum is σ = 2966622624. Its totient is φ = 637982880.

The previous prime is 1621540397. The next prime is 1621540451. The reversal of 1621540430 is 340451261.

It is a super-2 number, since 2×1621540430² = 5258786732249169800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1621540430.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1328522 + ... + 1329741.

It is an arithmetic number, because the mean of its divisors is an integer number (185413914).

Almost surely, 2^1621540430 is an apocalyptic number.

1621540430 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1621540430 is a deficient number, since it is larger than the sum of its proper divisors (1345082194).

1621540430 is a wasteful number, since it uses less digits than its factorization.

1621540430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2658331.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 1621540430 is about 40268.3551936257. The cubic root of 1621540430 is about 1174.8324324193.

Adding to 1621540430 its reverse (340451261), we get a palindrome (1961991691).

The spelling of 1621540430 in words is "one billion, six hundred twenty-one million, five hundred forty thousand, four hundred thirty".