1621390156 has 24 divisors (see below), whose sum is σ = 3015783680. Its totient is φ = 760566672.

The previous prime is 1621390139. The next prime is 1621390157. The reversal of 1621390156 is 6510931261.

It is not an unprimeable number, because it can be changed into a prime (1621390157) by changing a digit.

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, 95736 + ... + 111391.

Almost surely, 2^1621390156 is an apocalyptic number.

It is an amenable number.

1621390156 is a deficient number, since it is larger than the sum of its proper divisors (1394393524).

1621390156 is a wasteful number, since it uses less digits than its factorization.

1621390156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207253 (or 207251 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 1621390156 is about 40266.4892435385. The cubic root of 1621390156 is about 1174.7961393119.

The spelling of 1621390156 in words is "one billion, six hundred twenty-one million, three hundred ninety thousand, one hundred fifty-six".