101661020 has 48 divisors (see below), whose sum is σ = 237958560. Its totient is φ = 36255744.

The previous prime is 101661019. The next prime is 101661029. The reversal of 101661020 is 20166101.

101661020 = T₃₅₉ + T₃₆₀ + ... + T₈₆₈.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a self number, because there is not a number n which added to its sum of digits gives 101661020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101661029) 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, 1409 + ... + 14328.

It is an arithmetic number, because the mean of its divisors is an integer number (4957470).

Almost surely, 2^101661020 is an apocalyptic number.

101661020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

101661020 is an abundant number, since it is smaller than the sum of its proper divisors (136297540).

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

101661020 is a wasteful number, since it uses less digits than its factorization.

101661020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15782 (or 15780 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 101661020 is about 10082.7089613853. The cubic root of 101661020 is about 466.7147082061.

The spelling of 101661020 in words is "one hundred one million, six hundred sixty-one thousand, twenty".