1621430906 has 16 divisors (see below), whose sum is σ = 2446857600. Its totient is φ = 805820400.

The previous prime is 1621430891. The next prime is 1621430933. The reversal of 1621430906 is 6090341261.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 634331 + ... + 636881.

It is an arithmetic number, because the mean of its divisors is an integer number (152928600).

Almost surely, 2^1621430906 is an apocalyptic number.

1621430906 is a deficient number, since it is larger than the sum of its proper divisors (825426694).

1621430906 is a wasteful number, since it uses less digits than its factorization.

1621430906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4349.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 1621430906 is about 40266.9952442444. The cubic root of 1621430906 is about 1174.8059811836.

The spelling of 1621430906 in words is "one billion, six hundred twenty-one million, four hundred thirty thousand, nine hundred six".