102920421 has 16 divisors (see below), whose sum is σ = 141231104. Its totient is φ = 66619584.

The previous prime is 102920417. The next prime is 102920429. The reversal of 102920421 is 124029201.

It is not a de Polignac number, because 102920421 - 2² = 102920417 is a prime.

It is a super-2 number, since 2×102920421² = 21185226117634482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102920429) 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, 94140 + ... + 95226.

It is an arithmetic number, because the mean of its divisors is an integer number (8826944).

Almost surely, 2^102920421 is an apocalyptic number.

It is an amenable number.

102920421 is a deficient number, since it is larger than the sum of its proper divisors (38310683).

102920421 is a wasteful number, since it uses less digits than its factorization.

102920421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1980.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 102920421 is about 10144.9702315975. The cubic root of 102920421 is about 468.6340618513.

Adding to 102920421 its reverse (124029201), we get a palindrome (226949622).

The spelling of 102920421 in words is "one hundred two million, nine hundred twenty thousand, four hundred twenty-one".