1621938151 has 2 divisors, whose sum is σ = 1621938152. Its totient is φ = 1621938150.

The previous prime is 1621938137. The next prime is 1621938257. The reversal of 1621938151 is 1518391261.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1621938151 - 2⁵ = 1621938119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1621938151.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1621938751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810969075 + 810969076.

It is an arithmetic number, because the mean of its divisors is an integer number (810969076).

Almost surely, 2^1621938151 is an apocalyptic number.

1621938151 is a deficient number, since it is larger than the sum of its proper divisors (1).

1621938151 is an equidigital number, since it uses as much as digits as its factorization.

1621938151 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 37.

The square root of 1621938151 is about 40273.2932723412. The cubic root of 1621938151 is about 1174.9284763465.

The spelling of 1621938151 in words is "one billion, six hundred twenty-one million, nine hundred thirty-eight thousand, one hundred fifty-one".