1021561145142 has 16 divisors (see below), whose sum is σ = 2045506340592. Its totient is φ = 340123040000.

The previous prime is 1021561145117. The next prime is 1021561145183. The reversal of 1021561145142 is 2415411651201.

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, 99329859 + ... + 99340142.

It is an arithmetic number, because the mean of its divisors is an integer number (127844146287).

Almost surely, 2^{1021561145142} is an apocalyptic number.

1021561145142 is an abundant number, since it is smaller than the sum of its proper divisors (1023945195450).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1021561145142 is a wasteful number, since it uses less digits than its factorization.

1021561145142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198670863.

The product of its (nonzero) digits is 9600, while the sum is 33.

Adding to 1021561145142 its reverse (2415411651201), we get a palindrome (3436972796343).

The spelling of 1021561145142 in words is "one trillion, twenty-one billion, five hundred sixty-one million, one hundred forty-five thousand, one hundred forty-two".