1621017120157 has 16 divisors (see below), whose sum is σ = 1639454572080. Its totient is φ = 1602628416000.

The previous prime is 1621017120101. The next prime is 1621017120181. The reversal of 1621017120157 is 7510217101261.

It can be written as a sum of positive squares in 8 ways, for example, as 378162272601 + 1242854847556 = 614949^2 + 1114834^2 .

It is a cyclic number.

It is not a de Polignac number, because 1621017120157 - 2¹¹ = 1621017118109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621017120557) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 254833657 + ... + 254840017.

It is an arithmetic number, because the mean of its divisors is an integer number (102465910755).

Almost surely, 2^{1621017120157} is an apocalyptic number.

It is an amenable number.

1621017120157 is a deficient number, since it is larger than the sum of its proper divisors (18437451923).

1621017120157 is a wasteful number, since it uses less digits than its factorization.

1621017120157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9744.

The product of its (nonzero) digits is 5880, while the sum is 34.

The spelling of 1621017120157 in words is "one trillion, six hundred twenty-one billion, seventeen million, one hundred twenty thousand, one hundred fifty-seven".